This is an italian-style omelet with lots of color and taste. Frittatas differ from omelets in that the vegetables are mixed into the eggs rather than used as a filling. A frittata is cooked very slowly and is not folded over. Frittatas are not really difficult to make and this one, being loaded with vegetables, is especially good! I watched cookbook author Willan demonstrate making this on TV. She said any vegetables do well in a frittata.