Step 1

Preheat oven to 350 degrees F. Coat a 10- x 15-inch rimmed baking sheet with cooking spray.

Step 2

In a medium skillet over medium heat, melt butter; cook onion 8 to 10 minutes or until tender and golden.

Step 3

On a lightly floured surface, with a rolling pin, roll out dough to a 10- x 15-inch rectangle. With your fingertips, gently push dough up to the edges, forming a rim. If dough is sticky, dust it and your hands lightly with flour.

Step 4

Brush dough with egg then spread onion evenly over the top. Sprinkle with poppy seeds and Parmesan cheese.

Step 5

Bake 25 to 30 minutes or until golden. Remove to a cutting board, let cool slightly, then cut into squares and serve.