In a large bowl, combine beans, corn, onion, garlic, taco seasoning, salt, cilantro, egg, and bread crumbs. Mix well; add 1 tablespoon of the reserved black bean liquid if needed to add moisture to the mixture. Shape into 4 patties and place on prepared pan. Drizzle olive oil on top of the sliders and transfer pan to the oven. Cook for 20 minutes.