Place tomatoes, onion, and butter into small saucepan, and bring to a simmer. Cook over low heat until sauce has thickened and reduced to about half. (About one hour.)
Place sauce in blender, or food processor. Blend until smooth.
Preheat oven to 400°.
Unroll crust dough onto a baking sheet coated with cooking spray. Bake at 400° for 8 minutes. Remove crust from oven, and brush with 1/2 teaspoon oil. Rub crust with cut sides of garlic. Top with desired amount of sauce, and you mozzarella cheese. Bake for a few more minutes (just until cheese starts melting and gets bubbly).
Combine 1/2 teaspoon oil and vinegar, stirring with a whisk.
Top pizza evenly with basil leaves, salt, and pepper. Drizzle the vinegar mixture evenly over the pizza. Cut pizza into 8 pieces.