Start by bringing a large pot of salted water to a rolling boil. Carefully add dry elbow macaroni and cook for 8–10 minutes, or until tender but al dente. Drain and rinse under cold water until cool.

In a mixing bowl, whisk together mayonnaise, sour cream, lime juice, taco seasoning, salt, and black pepper until smooth.

In a large bowl, combine macaroni, black beans, sweet corn, red and green bell peppers, red onion, and cheddar cheese if using. Sprinkle in cilantro and toss everything gently.

Pour the creamy dressing over the salad and gently fold to coat all ingredients.

Cover and chill in the refrigerator for at least 1 hour before serving. Stir and adjust seasoning as needed before serving.