In a large bowl, mash beans with a potato masher or fork until they are mostly smooth, with some chunks remaining.
Add cereal, egg, onion, cilantro, jalapeño, lime juice, garlic, salt, and cumin; blend well. Let stand 15 minutes to firm, then shape mixture into 6 (4-inch) patties, or 12 (2-inch) football-shaped cakes.
In a large nonstick or cast-iron skillet, heat oil over medium-high heat. Add patties or cakes and cook, turning once, until well browned, about 3 minutes per side.