In a saucepan, combine refried beans, queso and salsa. Heat on medium heat and stir until combined.
Place 8 tostadas on a baking sheet. Top with a large spoonful of your bean mixture and spread to edges of the tostada. Add shredded cheese on top. Add black olives and your favorite taco sauce, if desired. Bake in a preheated oven at 350 degrees for 5-7 minutes.
You can also microwave 2 tostadas at a time for 1 minute if you don’t want to use an oven.