Mix the sour cream, mayonnaise, salt, pepper, and vinegar together to make the dressing. Add more salt and pepper to taste.
Stir 2/3 of the dressing into the peas until the peas are coated. Gently stir in the bacon, onion, cheese, and parsley until all combined
Taste and adjust seasonings. Cover with plastic wrap and refrigerate 2 to 4 hours before serving. (Pop the extra dressing in the fridge, too.)
Remove from the fridge and stir in the rest of the dressing to your liking. Sprinkle with more parsley before serving.
If you are wanting to cut down on the calories and such the switch out the sour cream for greek yogurt and substitute sour cream for the mayonnaise. Everything else is good for you and can eat it with a clear mind.