Using a trifle bowl or something similar, layer the ingredients as follows: lettuce, onion, peas, and eggs.
In a bowl, mix together mayo and garlic powder. Spread the dressing over the salad. Add a layer of bacon (we usually crumble it into smaller pieces, but strips will work too).
Cover the entire thing with the package of cheese.
Use tinfoil to cover the dish. Chill overnight.
Before serving, add a few pinches of salt and pepper, according to taste.