- Add the oil to a small frying pan over a low-medium heat, then add the chopped ham and leek, and stir until the leek has softened, about 3–4 minutes.
- In a bowl, beat the eggs with the yogurt, then mix in the pepper and half the cheese. Meanwhile, turn the grill on.
- Pour the egg mixture into the pan and mix quickly with a fork. Allow to cook for 1 minute, then stir again. Cook for another 1–2 minutes, constantly easing the edges of the frittata away from the sides of the pan.
- Sprinkle with the remaining cheese and place under the grill for 2–3 minutes until golden brown.
- Slide the frittata onto a plate, sprinkle with some chopped, fresh chives and enjoy. Alternatively, allow to cool and then refrigerate.
- Parmesan has a strong flavour, so you don't need to use very much to get a fantastic cheesy flavour, but with less fat.
- Store unused Parmesan in greaseproof paper inside a polythene bag in the fridge, as clingfilm makes it sweat.
- Use a small frying pan for this recipe.