Heat 1 tsp vegetable oil in a non-stick frying pan. Add the peppers and spring onions, and stir-fry for 3-4 minutes until soft. Tip them out of the pan into a bowl. Wipe out the pan with kitchen paper. Preheat the grill.

Beat the eggs and milk together. Heat a few drops of vegetable oil in the non-stick frying pan and pour in one quarter of the egg mixture. Let it flow over the surface and cook for 1-2 minutes to set the base. 

Sprinkle one quarter of the pepper mixture evenly over the surface, then grill for 1-2 minutes until set. Slide onto a warm plate.

Repeat with the remaining mixture to make four omelettes. Serve, seasoned with black pepper.