Preheat your oven to gas mark 6 (200C, 400F).

Cook the vegetables

Start by frying your onion.

Heat the oil in a medium frying pan over a medium heat.

Peel and finely chop the onion. Then add it to your oil and fry for 10 minutes, stirring occasionally so it doesn’t catch.

Cut the tomato into wedges and add it to your onion.

Fry for 5 minutes longer.

Prepare the eggs

Crack the eggs into a large bowl and season with a pinch of salt and grind of pepper.

Don’t add a lot of salt – you have a lot of salty ingredients in this frittata. But a little goes a long way in making sure the egg itself has flavour.

Beat with a fork until the yolks and whites are well combined.

Add all your remaining ingredients to the eggs.

Crumble the feta in.

Pit and slice the olives, and add them too.

Then tear in the basil.

Cook the frittata

Next, pour your egg mixture into the tomato and onion and stir.

Everything should be combined and the filling should be well distributed.

Fry your frittata until you can see that the sides have started to set.

Put it in the oven until cooked through.

It takes about 5 minutes more. Don’t overdo it – you’ll lose the creamy texture of the egg.

You know it’s done when you can press down on the top with a fork and no egg runs out.

Enjoy warm or at room temperature.