Preheat the oven to 400°F (200°C).

In a skillet over medium heat, cook the ground beef with the diced onion and diced bell pepper until the meat is browned and the vegetables are tender. Drain any excess fat from the skillet.

Stir in the garlic powder, Italian seasoning, salt, pepper, and ½ cup of the pizza sauce. Allow the mixture to simmer for approximately 3 to 5 minutes, then remove it from the heat.

Grease a deep cake pan or cast iron skillet. Roll out the pizza dough and carefully press it into the pan, ensuring the dough extends up the sides to form a deep dish crust.

Evenly layer half of the shredded mozzarella cheese on the bottom of the prepared crust. Top the cheese layer with the cooked beef mixture, then add the shredded cheddar cheese (if using), followed by the remaining shredded mozzarella cheese.

Spoon the remaining ½ cup of pizza sauce evenly over the top layer of cheese. Arrange the pepperoni slices and any additional toppings, such as sliced jalapeños or mushrooms, as desired.

Bake the pizza uncovered for approximately 35 to 40 minutes, or until the crust is golden brown and the cheese is melted and bubbly.

Allow the pizza to rest for 10 minutes prior to slicing and serving.