What happens when you take thinly sliced vegetables, layer them in a dish, add a rich red sauce, plenty of herbs, and a cheesy topping? You get this insanely delicious oven roasted ratatouille, aka “the vegetable dish that vegetable haters won’t be able to get enough of.” While this interpretation of ratatouille isn’t exactly traditional, I think you’re going to love it. And once you learn how to make ratatouille this way, you’ll want to make it all the time!
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“Easy to make, beautiful to look at, really inexpensive, very healthy and MUCH better than my stovetop ratatouille. My husband and I devoured it. Yum with a capital Y.”
Vicky
Easy Ratatouille recipe in the oven
Ratatouille is a classic French dish that’s rich, comforting, and perfect for sopping up with a piece of crusty artisan bread or ladling over a bowl of polenta. Like many traditional recipes, there are countless versions out there—and mine takes a bit of a twist.
Rather than stewing the vegetables together in a pot, I chose to make an oven roasted ratatouille, which is a common alternative to the stewed version. Not only is oven roasting the sliced vegetables super pretty, but it’s a little more hands-off than stewing vegetables in a pot, which I appreciate. I also added marinara sauce to the bottom of my casserole dish, which ends up mixing with the juices from the vegetables and creating the most delicious sauce (get some bread ready for dipping). Lastly, I topped with cheese, which definitely isn’t the norm for ratatouille, but it sure was delicious!
Recipe Tips & Variations
- This recipe is extremely flexible. I’ve given some approximate weight values for the vegetables below, but you can really use whatever size you have available and whatever you can squeeze into your baking dish. But a word of advice: once sliced, the volume of the vegetables always ends up being more than you estimated, so err on the side of smaller vegetables.
- I don’t peel my vegetables as the skins help hold their shape and add color to the finished dish. However, feel free to peel your veggies if preferred!
- Use soft veggies (and slice them evenly). While this recipe is my easy oven-roasted version, I kept the vegetables true to a classic ratatouille recipe by using eggplant, zucchini, tomatoes, and onions. If you want to change things up, you can mix in other soft veggies like red or orange bell peppers, sliced mushrooms, or other tomato varieties like beefsteak tomatoes. Just make sure everything is cut to about the same thickness so the layers cook evenly.
Oven Roasted Ratatouille
Cost $6.48 recipe / $0.81 serving
Ingredients
- 1 cup marinara sauce ($0.49*)
- 1 yellow onion (thinly sliced, (170g, 1¼ cup) $0.90)
- 1 eggplant (thinly sliced, (about 1 lb, 450g, 3 ½ cups), $1.56)
- 1 zucchini (thinly sliced, (about ½ lb, 227g, 2 cups) $0.74)
- 1 yellow squash (thinly sliced, (about ½ lb, 227g, 2 cups) $0.84)
- 3 Roma tomatoes (thinly sliced, (360g, 2 ½ cups) $0.87)
- 1 Tbsp olive oil ($0.18)
- ½ tsp dried basil ($0.25)
- ½ tsp dried oregano ($0.03)
- ⅛ tsp black pepper (freshly cracked, $0.03)
- ⅛ tsp salt ($0.01)
- 1 cup mozzarella (shredded, $0.97)
- 1 Tbsp fresh parsley (chopped (optional), $0.05)
Video
Instructions
- Gather all your ingredients and preheat the oven to 400ºF.
- Thinly slice the yellow onion. Slice the eggplant, zucchini, yellow squash, and tomatoes into ⅛-inch thick slices. Cut any pieces with a larger diameter into half-rounds.**
- Pour the marinara in the bottom of a large casserole dish. Sprinkle the sliced onions over top.
- Begin to line up the sliced eggplant, zucchini, squash, and tomatoes into the dish, standing on their sides, and in an alternating pattern until all of the pieces are used up. Drizzle the olive oil over the vegetables, then sprinkle the basil, oregano, salt, and pepper over top.
- Transfer the dish to the oven and roast the vegetables for 40 minutes. After 40 minutes, remove the dish from the oven and sprinkle the shredded mozzarella over top. Return the casserole dish to the oven for five minutes, or until the cheese is melted and creamy.
- After roasting, sprinkle the chopped parsley over top, then serve.
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Equipment
- 9×13 Baking Dish
Notes
Nutrition
Have you tried this recipe?Mention @budgetbytes or tag #budgetbytes on Instagram!How to Make Oven Roasted Ratatouille Step-by-Step Videos
Gather all of your ingredients: Preheat your oven to 400ºF. For this recipe, I used one small eggplant (about 1 lb.), one yellow onion, one yellow squash (about ½ lb.), one zucchini (about ½ lb.), and three Roma tomatoes. The eggplant, squash, zucchini, and tomatoes are the vegetables that will get layered pretty in the dish, while the onion will hide underneath in a base layer.
Slice vegetables: Thinly slice the eggplant, squash, zucchini, and tomatoes. You want everything to be similar in height when placed in the casserole dish, so for pieces with a larger diameter, you’ll want to slice those in half (I did this for the eggplant and larger ends of the squash and zucchini). Aim for ⅛-inch thick slices.
Thinly slice the onion. Spread 1 cup marinara in the bottom of a large casserole dish. Sprinkle the sliced onion over top.
Layer vegetables: Layer the vegetables in the dish standing up on their sides, like cards in a card catalog (wait, did I just date myself??). They do NOT need to be perfect. Just start squeezing them in as best you can. It’s nice to try to alternate them in a pattern, but once you get toward the end, you might have more left of one type of vegetable, so just start popping them in there anywhere they’ll fit.
Drizzle 1 Tbsp olive oil over top. Sprinkle ½ tsp dried basil, ½ tsp dried oregano, ⅛ tsp freshly cracked pepper, and ¼ tsp salt on top of the vegetables.
Transfer the dish to the preheated 400ºF oven and roast for 40 minutes.
After 40 minutes, remove the dish from the oven and sprinkle 1 cup of shredded mozzarella on top. Return the dish to the oven and bake for an additional 5 minutes, or until the cheese melts and looks creamy.
Garnish and serve: Top with 1 Tbsp chopped parsley (optional), then serve! This roasted ratatouille is so delicious…and it’s just begging for a beautiful baguette to bathe in it. Mmmmm. You’ve got to spoon some of that sauce from the bottom of the pan onto your plate!
Closer look? So pretty. I ❤️ vegetables!
Serving suggestions
Oven roasted ratatouille makes a delicious side dish for grilled or roasted meat. Try it with juicy herb roasted pork tenderloin. Or serve it next to garlic butter baked cod, where the flaky, buttery fish balances the ratatouille’s rich texture and tangy tomato notes. For something equally satisfying, I’d pair it with juicy baked chicken breasts. You could also serve this as part of a vegetarian meal by pairing it with something like a rich and creamy Parmesan risotto or serving it on top of a bowl of polenta!
Storage & Reheating
Store any leftovers in the fridge, in an airtight container, for up to 3-4 days. I usually reheat individual portions in the microwave until heated through. You can also freeze this dish for up to 3 months, but the veggies will turn out much softer once thawed and reheated. Let your oven roasted ratatouille cool completely before storing it in the fridge or freezer.
More Veggie Side Dish Recipes
Our Oven Roasted Ratatouille recipe was originally published 5/19/14. It was retested, reworked, and republished to be better than ever 10/27/25.
I adore eggplant–never tasted it as a child because even though my dad loved it, too, mom didn’t and never grew it or cooked it. Ratatouille, which I discovered as a new bride with Julia Child’s 1st cookbook in hand, is one of my summer treats. This version, a traditional tian, or, gratin, since it includes cheese, is no more fiddly than the traditional version of individually diced and sauteed veggies–and much prettier. I love it! I don’t think eggplant freezes well, but since the leftovers disappear within a few days, I never tried to freeze them. When I make the more traditional version, I add some chopped Kalamata olives making a dish that’s kind of a hybrid between ratatouille and caponata, but that salty bite is delicious with the blander flavors of eggplant and squashes. I don’t like this dish “crispy,” but I do want it well cooked.
After reading the comments, I suggest that it may take more or less time in the oven than the recipe indicates! Ovens and individual preferences vary, so if a dish needs more time, don’t blame the recipe, but give it more time. Common sense rules always!
Actually, Julia Child’s 1st volume of French Cooking does construct Ratatouille like this, minus cheese. But every slice is sauteed in oil, as are the sliced onions and peppers–no possibility of an undercooked final product. I can’t remember where i first encountered the dice and saute instructions, which usually been my usual method.
I’ve been making this recipe for years! Before I bake it, I just savor the “colors of summer. It’s my go-to: “I have too much squash, zucchini, eggplant, etc…” recipe! SOOOOO good with my homemade sourdough! Thanks, Beth! You never disappoint!
I dislike egg plant. I’m neutral on summer squash and zucchini. For some reason this was awesome. My wife and I made it together and as it came together, I became a believer. Best vegetarian dish I’ve ever had, hands down.
I really enjoyed this recipe! So fresh & easy to put together (thanks to the mandolin my mom gave me.) I baked it for 40 min plus 5 after adding cheese & it came out perfectly! My boyfriend & I enjoyed it for dinner & paired with just some simple toasty buttered bread. I did a modify a couple things though.
– I cut the veggies to 1/4”
– I used 2 beef steak tomatoes because the Roma tomatoes looked sad that day
– I used 1/2 tsp salt & 1/4 tsp ground black pepper (plus more to taste after baking was finished)
– I topped it off with fresh basil, thyme, & parmesan cheese instead of parsley
10/10 will make again!
I really like this dish, because I was able to eat something both delicious, hearty and vegetarian. I recommend wetting the eggplants though, not drying them because crispy food hurts my teeth… and if u don’t like your sauce too watery just blend like a teaspoon of some flour into the sauce. that is all my personal choices though. This dish is truly an inspiration to me though.
This recipe sounded delicious and I was super excited to try it, but it was a complete disappointment. The onions tasted raw and the eggplant was rubbery and underdone. The first unsuccessful recipe I’ve had from Budget Bytes.
I tried this recipe too, but from my experience with eggplant I have to wet it, not dry it before slathering oil all over it.. i covered it as well til the end to make the top crispy and i think the next time i will have to add a teaspoon of flour to thicken the sauce a bit and catch any water that falls from the veggies.
This is a GREAT recipe for the summer veggies! I first used it about 10 years ago when my daughter belonged to a basket program, & we got lots! of zucchini & needed to find a way to use it….we found this recipe & it has been a family favorite!
I made this with marinara sauce, two different types of squash (zucchini and patty pan), sliced onion and sliced tomato and topped it with cheddar cheese and parmesan cheese. It was delicious. I will enjoy making it again as summer progresses and the mix of garden produce changes.
yes
Looks tasty
This looks so delicous to make
(Cant spell)
Easy to make, beautiful to look at, really inexpensive, very healthy and MUCH better than my stovetop ratatouille. My husband and I devoured it. Yum with a capital Y.
My family LOVED this recipe! It was quick to pull together, inexpensive, and beautiful. I served it alongside crusty “pan de agua” for a complete vegetarian meal. This one is going on my meal rotation. Well done! 👏🏽
Delicious! Much tastier than the stovetop ratatouille I’ve been making for years, and it’s got a nice crunch to it, too. Thanks!
Sooo good! I added some bell peppers in and mixed a little basil pesto in with the malted sauce! Divine!