In a medium saucepan, bring the butter to medium heat until melted. Add the chopped apples and stir to coat. Cook uncovered for 4-5 minutes, stirring occasionally. In a small dish, combine the cornstarch and water and stir together. Pour the cornstarch mixture, 2 tablespoons of the sugar, and ½ teaspoon of the cinnamon into the pot with the apples and stir to combine. Cover the saucepan and reduce heat to low. Simmer for 3-4 minutes until the mixture is thick and apples are tender. Remove from heat.

Preheat the oven to 425 degrees. Line a baking sheet with parchment paper and mist with cooking spray. Set aside.

Pour some water into a small dish and set aside. On a clean, flat surface, place an egg roll wrapper, corner facing toward you (like a diamond) and put 3 tablespoons of the apple mixture on the center of the wrapper. Spread the mixture in a horizontal line from the left corner to the right corner of the wonton wrapper, leaving ½ inch or so of space on each side. Fold the bottom corner closest to you up over the ingredients and give it a 90 degree roll. Fold the side corners in and tuck them as you give the filled section another 90 degree roll. Dip your finger in the dish or reserved water and lightly wet the edges of the remaining top corner of the wrapper. Finish rolling the filled egg roll over the wet corner so that it adheres. Place wrapped egg roll onto the prepared baking sheet. Repeat with remaining ingredients.

Stir the remaining tablespoon of sugar and ¼ teaspoon of cinnamon together in a small dish. When all the egg rolls are put together and on the baking sheet(s), mist the tops of them with cooking spray. Sprinkle about half of the cinnamon-sugar mix over the tops of the misted egg rolls and rub it in if necessary. Flip the egg rolls over, mist with cooking spray, and do the same on the other side with the remaining cinnamon-sugar mixture. Place the baking sheet in the oven and bake for 7 minutes. Flip each of the egg rolls over and bake for an additional 7 minutes until the wrappers are golden.