Mely Martinez’ Black Bean Tostadas

Tostadas are the ultimate comfort food for Mely Martinez, food blogger and author of “The Mexican Home Kitchen.” She favors cooking dried beans, but canned beans and store-bought tostadas (corn tortillas that are fried flat) allow this recipe to come together easily and with amazing speed. Martinez prepares her black beans simply, without added spices, but we like them spiked with ground cumin. We’ve kept the cumin optional, so the choice is yours whether or not to add it. Either way, the tostadas offer a delicious contrast between crunchy and creamy, with salty notes from the queso fresco, coolness from the lettuce and creaminess from the Mexican crema (or sour cream).