Get some kind of bread that doesn't have whey or other dairy products in it. Find some soy cheese without casein or other dairy products in it. Buy some vegan pepperoni. Buy a small can of sliced black olives or other vegan topping. Get a small can of crushed tomatoes.
Cook the bread in the oven until its slightly crisp.
Put some crushed tomatoes onto the bread and then add the other toppings.
Microwave it or put it back in the oven to melt the cheese.
Enjoy.