In a 9" non-stick skillet cook the onion and the bell pepper with salt & pepper to taste in 1 tb of the oil over mod. Low heat, stirring, until the bell pepper is tender. In a bowl whisk together the eggs, ham, 1/3 cup of the swiss cheese and salt & pepper to taste. Add the bell pepper mixture and stir until combined well. In the skillet heat the remaining 1/2 tb oil over moderate heat until it is hot but not smoking, pour in the mixture, distributing the ham & bell pepper evenly, and cook the frittata, without stirring, 8-10 minutes, or until the edge is set but the center is still soft. Sprinkle the remaining 1/3 cup Swiss cheese over the top. If skillet handle is plastic, wrap it in a double thickness of foil. Broil the frittata under a preheated broiler about 4" from the heat for 2-3 minutes, or until the cheese is golden, and let it cool in the skillet for 5 minutes. Slide the frittata onto a serving plate, cut it into wedgges, and serve it warm or at room temperature. From Best of Gourmet