Frittata

Preheat the oven to 190C and choose a pan that can move safely from the burner to the oven. Stir 8 eggs with 80 ml milk and 0.8 teaspoon salt only until blended. Vigorous whisking adds excess bubbles, which can leave a coarse rather than tender interior. Thinly slice 90 g onion, halve 120 g cherry tomatoes, and shake all excess water from 80 g spinach so it does not thin the eggs. Warm 1 tablespoon olive oil in the pan over medium heat. Cook the onion for about 3 minutes, stopping when it is soft and translucent rather than deeply browned. Add the spinach and tomatoes for only 1 minute. The spinach should barely wilt and the tomatoes should warm without collapsing. Pour the egg mixture evenly over the vegetables and do not stir it hard into the filling. Lower the heat to medium-low and leave the pan undisturbed for about 3 minutes. When the rim has set and begins to pull slightly from the pan, scatter 80 g cheddar over the surface. Transfer the pan to the oven and bake for 10 minutes. Test the center with a light press; it should spring back gently rather than feel liquid underneath. Rest the finished frittata for 2 to 3 minutes before slicing so the egg and vegetables hold together. Leftover wedges can also be chilled and used as a sandwich filling.