Melt the butter on low heat in the cast-iron skillet (or medium skillet).
While the butter is melting, peel and cut the apples into medium-sized wedges.
After the butter is melted and the apples are cut, turn the heat to medium. Sprinkle the sugar, cinnamon, nutmeg, and salt into the skillet. Stir to combine.
Add the sliced apples and stir to coat.
Cook the apples, stirring occasionally, for 25-30 minutes until syrupy and the apples are tender.
*Granny Smith are some of the best for fried apples due to their price, firmness, and tartness. Other apples that hold their shape well, such as Honeycrisp, Fuji, Gala, Pink Lady, or Golden Delicious, also work. Five apples were perfect, but if your apples are smaller, you may need one or two more. My apples weighed 1250g total uncut.**You can use brown sugar instead of granulated sugar or a mixture of the two.