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Order
Sometimes I brush the crust lightly with olive oil, then I 1) put the sauce
 on, 2) sprinkle with freshly chopped garlic or powdered garlic, 3) sprinkle
 with dried oregano, 4) top with cheese, 5) top with mushrooms or vegetables.

I put a layer of cheese on before I add my
 toppings. It gives it some sticking power.
I put the sauce on the crust next,
Then add the meat mixture. Then I top with fresh tomatoes, pepperoni and my
choice of gf cheeses. I seldom use any other seasoning than what is in the
Prego sauce.
Definitely use fresh mushrooms. The canned ones are terrible compared to
 fresh.

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