Step 1

In a large skillet, melt 4 Tbsp butter over medium heat. Add sliced apples and cook, stirring occasionally until lightly browned (6-8 min). Reduce heat to low and stir in 1/4 cup brown sugar and 1 tsp cinnamon. Continue to simmer, stirring occassionally until apples are soft and caramelized (5 min).

Step 2

Lightly dust a sheet of parchment paper with flour. Place your thawed puff pastry dough over it and roll it out slightly to flatten the top (9 1/2 x 10 1/2 inches). Cut puff pastry dough in half down the center to make two pieces (each 4 3/4 x 10 1/2 inches)

Step 3

Arrange apples in a tight row lengthwise down the middle of one puff pastry sheet leaving a one inch border on all sides. Pour remaining syrup from the apples over the top of the apples. Brush your beaten egg around the edges of your pastry. Top with the second pastry sheet and press down on the edges to seal.

Step 4

Cut 6 (1-inch wide) slits down the center of your pastry to create vents.

Step 5

Brush the pastry with egg wash and sprinkle the top generously with coarse sugar. Bake at 400˚F for 15-17 min or until top is golden brown.