In a large, deep, non-stick sauté pan, heat 15 mL (1 tbsp) olive oil on medium-high heat and brown the mushrooms and sliced peppers for 4-5 minutes. Season with salt and pepper and set aside.
Reduce heat to medium, add the rest of the olive oil to the pan, and sauté the garlic for 1 minute. Add the Italian sausage meat, increase heat to medium-high and cook the meat until it separates into little pieces and is fully browned.
Add the tomato sauce, tomato paste, sugar, thyme, basil, oregano, parsley, hot pepper and beef stock. Stir the sauce ingredients thoroughly and add the pasta, making sure that it is fully submerged in the liquid.
Bring to a boil, lower heat and cover to let simmer for 10-12 minutes. Stir occasionally to make sure the pasta doesn’t stick.
Preheat the oven to 230 oC (450 oF).
When the pasta is al dente, take the sauté pan off the heat and garnish with mushrooms and green peppers. Sprinkle with Cheddar and Parmesan cheeses, then finish with pepperoni.
Bake for 2-4 minutes until the cheese becomes golden.