Begin by boiling a large pot of salted water over high heat. Once it reaches a rolling boil, add the elbow macaroni and cook for about 8–10 minutes until al dente. Drain and rinse the pasta under cold running water.

While the pasta is cooling, prepare the vegetables by dicing the red bell pepper and slicing the green onions. Drain and rinse the black beans and corn.

In a mixing bowl, whisk together the sour cream, mayonnaise, lime juice, taco seasoning, and garlic powder until smooth.

In a large serving bowl, combine the cooled elbow macaroni with the prepared vegetables and pour the dressing over it.

Gently toss all the ingredients together and refrigerate for at least one hour.

Before serving, stir the salad gently again and adjust the seasoning if necessary.