Place the chopped lettuce in the bottom of a large straight-sided glass bowl.
Press some egg slices around the edge of the bowl, then place the remaining slices in the center.
Sprinkle the bacon over the egg layer, reserving a little for garnish.
Press the cherry tomatoes around the edge of the bowl, then place the remaining tomatoes in the center.
Sprinkle on the red onion, peas, and shredded cheddar cheese, reserving a little cheese for garnish.
In a small jar or bowl, mix together the mayonnaise, sour cream, sugar, salt, and pepper until smooth.
Pour the dressing evenly over the top of the salad, leaving a small rim of cheese exposed around the edge.
Cover tightly with plastic wrap and refrigerate for at least 4 hours before serving.
Garnish with the reserved bacon, cheese, and chopped green onions just before serving.