Dry the beans: After rinsing, spread the black beans on a clean kitchen towel or paper towels and pat them dry. The drier they are, the crispier the patties will be.
Mash the base: Add beans to a large bowl.
Use a fork or potato masher to mash until about 2/3 of the beans are smashed and 1/3 remain mostly whole for texture.
Add aromatics and seasoning: Stir in the minced onion, garlic, chili powder, cumin, smoked paprika, salt, and pepper.
Bind the mixture: Mix in breadcrumbs (or oats), tomato paste, and soy sauce. Add the egg (or flax egg). Stir until the mixture holds together when pressed.
If it’s too wet, add more breadcrumbs a tablespoon at a time.
Chill to firm up: Cover and refrigerate for 15–20 minutes. This helps the patties keep their shape in the air fryer.
Shape the patties: Divide the mixture into 4 large or 5 smaller patties, about 1/2-inch thick. Press the edges so they’re smooth and compact.
Preheat the air fryer: Set to 375°F (190°C) for 3 minutes.
Lightly brush the basket with olive oil or use a small piece of parchment designed for air fryers.
Air fry the first side: Brush or spray the tops of the patties with a little oil. Place them in the basket without crowding. Cook for 7–8 minutes.
Flip and finish: Carefully flip the patties, brush with a bit more oil if you like, and air fry 5–7 more minutes, until the edges are crispy and the centers feel set.
Optional cheese melt: Add a slice of cheese during the last minute and close the basket to melt.
Toast buns and assemble: Toast the buns briefly in the air fryer or a skillet.
Build with your favorite toppings and sauces. Taste and adjust salt if needed.