Step 1

Position a rack in lower third of oven; preheat to 425°F. Coat a large baking sheet with cooking spray.

Step 2

Heat 1 tablespoon oil in a large skillet over medium heat. Add bell peppers and onion; cook, stirring occasionally, until softened, about 5 minutes. Remove from heat.

Step 3

Roll dough out on a lightly floured surface into a rectangle approximately 14 by 10 inches. Spread pesto over the dough, leaving a 1/2-inch border. Top with the bell pepper mixture, spinach, banana peppers and cheese. Starting at a long side, tightly roll the dough into a cylinder. Pinch and tuck both ends closed to contain the filling. Using two spatulas, carefully transfer the stromboli seam-side down to the prepared baking sheet. Brush with the remaining 1 teaspoon oil and sprinkle with sesame seeds.

Step 4

Bake until the crust is beginning to brown, 15 to 20 minutes. Let stand for 5 minutes, then slice.