Prepare your ingredients by slicing the bell peppers into strips, chopping the onion finely, and mincing the garlic. Cut the Italian sausage into bite-sized pieces.

In a large skillet, heat 2 tablespoons of olive oil over medium heat. Add the sausage pieces and cook for 6-8 minutes until golden brown.

Remove the sausage from the skillet, leaving the drippings. Add the bell peppers and onion to the skillet and sauté for about 8 minutes until softened. Add the garlic and cook for another minute.

Return the cooked sausage to the skillet. Pour in the crushed tomatoes and add the herbs, salt, and pepper. Stir and simmer for 10-15 minutes.

Preheat your oven to 375°F (190°C). Transfer the mixture to a baking dish if required, sprinkle with Parmesan, and bake for 10-15 minutes until melted and bubbly.

Let the dish cool for a few minutes. Top with chopped parsley or basil and serve alongside crusty bread.