Heat 1 tablespoon of olive oil in a large skillet over medium heat. Add the black beans, cumin, chili powder, and salt. Cook for 3 to 4 minutes, stirring often, until the beans are warmed through and lightly mashed.

Lay one tortilla flat. Spread half the bean mixture over it, sprinkle with half the cheese, and top with a second tortilla. Repeat with the remaining ingredients to make a second quesadilla.

Add the remaining tablespoon of olive oil to the skillet. Cook each quesadilla for 2 to 3 minutes per side until the tortillas turn golden and the cheese melts. Remove from the skillet and let them rest for 1 minute.

Spoon the sour cream into a small zip-top bag and snip off one corner. Pipe concentric circles on each quesadilla, then drag a knife from the center outward in several lines to form a web pattern. Cut each quesadilla into 6 to 8 slices.