Make the Dressing: In a small mixing bowl, whisk together the olive oil, lime juice, lime zest, cilantro, cumin, and garlic until smooth and fragrant.
2 ½ tablespoons olive oil, 2 tablespoons fresh lime juice, 1 teaspoon lime zest, ¼ cup finely chopped fresh cilantro, ½ teaspoon ground cumin, 1 ½ teaspoons minced garlic
Build the Salad Base: In a large mixing bowl, add the brown rice, black beans, tomatoes, bell pepper, jalapeño, corn, red onion, and avocado if using.
2 ½ cups cooked brown rice, 1 can black beans, 2 medium Roma tomatoes, ¾ cup chopped bell pepper, 1 small jalapeño, 1 cup frozen corn, ½ cup chopped red onion, 1 avocado
Dress and Season: Pour the cilantro-lime dressing over the rice mixture and gently toss until everything is evenly coated. Season with salt and freshly ground black pepper to taste.
Salt, Freshly ground black pepper
Serve or Chill: Serve immediately, or refrigerate for 20 to 30 minutes to let the flavors blend. Serve chilled or at room temperature as part of a Cinco de Mayo spread alongside tacos, grilled meats, or party appetizers.