01 -
Heat 15 ml olive oil in a large skillet over medium heat. Add sliced onions, bell pepper, garlic, Italian seasoning, salt, and black pepper. Sauté until vegetables are caramelized and tender, about 8 to 10 minutes. Remove from the skillet and set aside.
02 -
Increase heat to high. Add 15 ml olive oil to the same skillet. Sear beef slices for 2 to 3 minutes until browned but still tender. Season with salt, black pepper, and red pepper flakes, if using. Remove from heat.
03 -
Preheat oven to 200°C. On a lightly floured surface, stretch the pizza dough into a 30 x 40 cm rectangle.
04 -
Evenly sprinkle shredded mozzarella and grated Parmesan over the dough, leaving a 2.5 cm border. Distribute the steak and sautéed vegetables on top.
05 -
Starting from the long side, tightly roll the dough into a log. Pinch the edges and ends to seal completely.
06 -
Transfer the log seam-side down to a parchment-lined baking tray. Whisk egg with water and brush the mixture over the dough. Slice 3 to 4 vents on top to allow steam to escape. Bake for 20 to 25 minutes or until the crust is golden brown.
07 -
Allow the baked stromboli to rest for 5 to 10 minutes before slicing. Serve warm, accompanied by marinara sauce for dipping.