In a bowl, whisk eggs and milk until frothy; pour into lightly oiled Omelet Maker.
Top egg mixture with cheese and salsa.
Close lid; microwave on high 2–3 min.
Loosen omelet with a Flipper, flip onto a plate, and serve topped with guacamole, if desired.
Whisk eggs and milk until frothy.
In a lightly oiled frying pan, add eggs and stir, bringing edges into middle, until set.
Remove pan from heat and top half the omelet with cheese. Fold the other side over the filling and slide onto a plate. Top with salsa and guacamole, if desired.