Open the can of black beans with a can opener, then pour them into a colander and rinse thoroughly under cold water until the water runs clear. Pat them dry gently with a towel or let them drain completely.
Finely dice the red onion and the bell pepper, creating small, colorful pieces that add crunch and freshness to the salad.
Transfer the rinsed beans, chopped onion, and bell pepper into a large mixing bowl, combining them evenly.
Squeeze fresh lime juice over the mixture, aiming for about two tablespoons, and add the olive oil if using. These will brighten and enhance the flavors.
Sprinkle in salt and freshly cracked black pepper to taste, then gently stir everything together with a spoon or spatula until well coated and evenly mixed.
Finely chop the fresh cilantro and fold it into the salad just before serving for a burst of herbal freshness.
Taste the salad and adjust seasoning if needed—add more lime for brightness or salt for depth. Let it sit for 10-15 minutes to allow the flavors to meld.
Serve the black bean salad at room temperature or chilled, garnished with extra herbs if desired. Enjoy this fresh, flavorful dish any time you need a quick, satisfying bite.