Wash and slice apple into 8 chunky slices and set aside. Chop nuts and set aside.
Line a baking sheet with parchment paper. Open the crescent rolls and lay out 8 triangles of dough. Melt 2 Tbsp butter in the microwave and brush each triangle with melted butter.
Sprinkle each triangle with cinnamon sugar, and chopped nuts. Reserve some of the cinnamon sugar for sprinkling on top.
Add an apple slice to each crescent roll and roll the dough into a crescent around the apple slice. Brush with any remaining butter and sprinkle with remaining cinnamon sugar.
Bake at 350°F for 15 minutes, until golden brown. Serve warm, and top with vanilla ice cream and chocolate sauce if desired.