Stir together the pumpkin puree, pumpkin pie spice, and brown sugar in a bowl.
Unwrap the graham crackers and place them in a gallon sized zip top bag. Crush the crackers with a rolling pin.
Layer the graham crackers, seasoned pumpkin puree, and yogurt into four containers. Feel free to create the layers in any order. My layers went as follows: 2 Tbsp graham, 3 Tbsp pumpkin, 2 Tbsp graham, 1/4 cup yogurt, 2 Tbsp graham, 3 Tbsp pumpkin, top with graham.
Either enjoy immediately or refrigerate for up to 5 days.