Rub steak with lime juice, oil, cumin, and salt. Let stand 15 minutes while a griddle heats over high heat.
Cook steak 3 to 5 minutes per side until browned and thickest section reaches 145°F.
Rest steak 5 minutes; slice thinly across the grain.
Split bolillos; toast cut sides on griddle 1 to 2 minutes until crisp.
Spread bottom halves with warm beans; spread tops with crema.
Layer steak, Oaxaca, avocado, tomato, and pickled jalapeños over beans.
Close tortas; press gently. Serve with bread crisp and cheese softened.