In a medium sized pot, heat canola oil, and cook the Italian sausage until browned.

Place the cooked sausage in a bowl and set aside.

Add the onion and garlic to the same pan, and cook until the onions are translucent.

Add the mushrooms and bell peppers, and cook until tender.

Deglaze the pan with the vegetable stock and add the sausage back into the pot.

Add the tomato paste, diced tomatoes, tomato sauce, and seasonings, and bring to a boil.

Reduce the heat to a simmer, and let the sauce reduce for approximately 30 minutes, or until it has reached a thick chili-like consistency.

To assemble, cut a horizontal line, from top to bottom, down the center of each individual bag of Chili Cheese FRITOS^®. Make perpendicular slits to the initial cut, to create a flap that can be pulled back to reveal the FRITOS^® chips. Pour enough of the Pizza Sauce to coat all of the FRITOS^®, and then garnish with diced mushrooms, pepperoni, bell peppers, and sliced olives. Finish with a sprinkle of the oregano, mozzarella cheese and parmesan cheese. An additional sprinkle of red pepper flake may be added to create a spicier Pizza Supreme Frito Pie.