Preheat the oven to 400 degrees F and line the baking sheet with foil. Put olives, sun-dried tomatoes, and oil in the food processor and pulse until it creates a paste.
Flour your surface and rolling pin, then roll the pizza dough until it becomes a 14x10-inch rectangle.
Spread the tomato paste over the dough, leaving a border measuring an inch.
Add the cheese on top of the dough, then top it off with the spinach and red peppers.
Fold one once of the dough over the filling. Then, fold its long ends on top of the sauce. Make sure to pinch the dough's corners.
Roll the dough very tightly. Brush it with a beaten egg, pinching the seam for sealing.
Put the roll on top of the baking sheet (seam side down) and brush the surface with beaten egg. Make a few slices in the top.
Bake the roll for half an hour or when the bread is golden in color and sound hollow if tapped.
Remove the roll from the oven, loosen the stromboli's bottom from the foil. Transfer it to a cutting board and let it cool before serving.