For the omelet, dice the tomatoes and cut the cooked ham into strips. Whisk the eggs with the water and the frozen herbs and season with salt and pepper.
Heat the olive oil in a non-stick frying pan (24 cm diameter), cover and let the egg mixture set for about 5 minutes, then remove and keep warm.
Fry the tomatoes and ham in the remaining oil, season with salt and pepper and add to the omelet.
Serve the hot omelet with freshly chopped basil.
The omelet goes well with a green salad. If you like, you can use prosciutto instead of ham. With fresh chopped herbs the omelet becomes even tastier.