1. Preheat oven to 400º. Stir together salsa and cilantro. Spread beans on tostada shells. Place shells on a jelly-roll pan; top with brisket, onion, and salsa mixture.
2. Bake at 400º for 8 to 10 minutes or until thoroughly heated. Serve immediately with desired toppings.
*Chopped grilled steak or pot roast may be substituted.