Combine green pepper, jalapeno pepper, onion, tomato, cilantro, lemon juice and salt in a small bowl; stir to mix well. Cover salsa and refrigerate. (The salsa can be served on its own.)
Add enough vegetable oil to a medium-size skillet to come to a depth of 1/2 inch. Heat the oil until hot but not smoking.
With tongs, carefully slip a tortilla into the hot oil; cook until the underside is golden brown, about 45 seconds. Turn the tortilla over; cook until golden brown, another 45 seconds. Using the tongs, transfer the tortilla to a double thickness of paper toweling to drain. Repeat the frying with the remaining tortillas and drain.
To serve, spread each tortilla with the black beans, dividing equally. Top the beans with a dollop of salsa and sour cream, dividing equally.