Heat oven to 375. Line baking sheet with parchment paper.
In a small bowl, toss apple slices in 1 tablespoon of melted butter; set aside.
In a small bowl, mix brown sugar and apple pie spice.
Separate crescent roll triangles and spread brown sugar mixture over each triangle.
Place one apple slice on each triangle and drizzle caramel sauce on top; wrap dough around apple.
Brush croissants with remaining melted butter. Bake for 10-12 minutes.
For the glaze:
Mix 1 ½ tablespoons powdered sugar with 1-2 tablespoons milk and ½ teaspoon vanilla extract. Drizzle over crescent rolls.