In a medium nonstick pan with an oven proof handle, heat olive oil until hot, but not smoking, add the potatoes, pancetta, and garlic and "fry" until golden on all sides. Add peas.
In a small bowl, whisk the egg whites with the whole eggs. Add the eggs, season with salt and pepper and cook over medium low heat, occasionally sliding a spatula around the edges of the pan to loosen the frittata as it cooks. Cook until just set. Sprinkle with cheese and place under the broiler until the top is golden brown, about 1 to 2 minutes.