In a large mixing bowl, combine 2 cups of thawed frozen peas, 1 cup of diced cheddar cheese, 1 cup of chopped celery, 1 cup of chopped red bell pepper, and ½ cup of finely chopped red onion. Mix gently until evenly distributed.

In a separate medium bowl, whisk together ¾ cup of mayonnaise, ½ cup of sour cream, 2 tablespoons of apple cider vinegar, 1 tablespoon of sugar, and salt and black pepper to taste. Whisk until smooth.

Pour the creamy dressing over the salad ingredients and gently toss to combine without mashing the peas.

Cover with plastic wrap or transfer to a sealed container and refrigerate for at least one hour to allow flavors to meld.

Before serving, stir the salad gently and present it in a serving bowl or on individual plates.