Cut the bacon slices into square pieces. Fry the pieces until well-cooked, then drain on paper towels.
Peel the potatoes, then grate them. To prevent the grated potatoes from discoloring while you prepare the other ingredients, you can put them into a bowl of cold water. When you're ready to use them, be sure to drain well and squeeze them dry.
Grate the cheese & mince the onion.
Butter a 9x13 inch shallow baking dish. Preheat the oven to 350F F.
Beat the eggs in a large bowl. Add all the other ingredients and stir.
Pour the mixture into the baking dish and bake in the preheated oven for about 45 minutes, or until the eggs are cooked.