Preheat the oven to 450°F (230°C). Lightly grease a 12×17-inch sheet pan with olive oil.
In a small bowl, combine the active dry yeast, granulated sugar, and warm water. Stir gently and let it sit for 5 minutes until the mixture becomes foamy.
In a large mixing bowl, whisk together the all-purpose flour and salt.
Add the yeast mixture and 2 tablespoons of olive oil to the flour mixture. Stir with a wooden spoon until a dough forms.
Turn the dough onto a lightly floured surface and knead for about 5 minutes until smooth and elastic.
Place the dough in a lightly oiled bowl, cover with a clean kitchen towel, and let it rise in a warm place for 10 minutes.
After rising, transfer the dough to the prepared sheet pan. Using your hands, stretch and press the dough evenly to cover the entire pan.
Spread the tomato sauce evenly over the dough, leaving about a 1/2-inch border around the edges.
Sprinkle the shredded mozzarella cheese evenly over the sauce.
Distribute the sliced bell peppers, mushrooms, and black olives evenly over the cheese.
Sprinkle dried oregano, garlic powder, and crushed red pepper flakes over the toppings.
Bake the pizza in the preheated oven for 18 to 20 minutes, or until the crust is golden brown and the cheese is melted and bubbly.
Remove the pizza from the oven and let it cool for 5 minutes before slicing and serving.