Start by mashing the ripe avocado in a medium bowl using a fork until it’s as smooth or chunky as you like.
Mix in the fresh lime juice to keep the avocado bright and fresh.
Add the drained black beans, corn, chopped red onion, and cilantro to the bowl with the mashed avocado.
Sprinkle cumin, chili powder, salt, and black pepper over the mix, then gently fold everything together to keep the beans mostly whole.
Warm the tortillas to make them soft and easier to roll, either in a skillet for 15-20 seconds each side or wrapped in a damp towel in the microwave for 30-45 seconds.
Place one tortilla flat and spoon a quarter of the filling into the center, shaping it lengthwise but leaving space at the edges.
Fold the short sides of the tortilla inward, then roll from the edge closest to you tightly over the filling until sealed.
Repeat with remaining tortillas and filling.
Serve the burritos immediately while warm; slice diagonally for a nice presentation or serve whole.
