In a medium bowl combine diced apples, brown sugar, cinnamon, and melted butter. Stir to combine and set aside.
Using a 1-tablespoon scoop, scoop out rounded balls. Make a well in the center and place a heaping teaspoon of the apple mixture inside. (Avoid the liquid in the bowl.) Form the rest of the cookie around the apple filling and place them close together on one of the cookie sheets.
Mix the 3 tablespoons of sugar and the cinnamon in a wide bowl. I like to use a fork but a small whisk also works.
Roll balls of dough in the cinnamon-sugar mixture. Place 2 inches apart on parchment-lined baking sheets.
Bake 10 to 12 minutes. Carefully remove immediately from baking sheets and place on a cooling rack.