Add mayonnaise, sour cream, apple cider vinegar, Dijon mustard, garlic powder, salt, and pepper to a bowl. Mix until smooth.
In a large bowl, combine peas, cauliflower, bacon, cheddar cheese, and red onion.
Pour the dressing over the salad ingredients and gently mix until everything is coated.
Cover and refrigerate for at least 30 minutes before serving.
Give the salad a quick stir before serving and adjust seasoning if needed.