Prepare dressing: In a large bowl, whisk together 1/2 cup mayonnaise, 1/2 cup sour cream, 1 teaspoon sugar, 1 teaspoon apple cider vinegar, 1/2 teaspoon kosher salt, and 1/4 teaspoon pepper.
Prepare salad: Add 16 ounces frozen peas, 2 hard boiled eggs(peeled and chopped), 6 ounces bacon(cooked crisp and chopped), and 1/2 cup cheddar cheese to the large bowl with the dressing. Gently fold to combine. To keep them crisp, hold off on folding in the 1 cup fried onion pieces just before serving.
Serve: As garnish, top with reserved peas, some additional crumbled bacon, more fried onion pieces, or chopped chives or scallions just before serving. Enjoy!