Make-Ahead
Onion mixture can be made a day in advance. Cool completely, then cover and refrigerate until ready to use.
Variation - Caramelized Onion Pizza
Substitute 1 pkg. (1 lb.) frozen pizza or bread dough, thawed, for the pizza crust. Do not prebake dough. Press into rectangle, then top with cheese, onions and olives as directed. Bake in preheated 425°F-oven for 25 minutes or until edges of crust are golden brown.