Wash and clean the zucchini. Slice it in halves and cut in 1/2 cm thick pieces. Chop the garlic and the onion.
In a frying pan heat the olive oil over medium heat. It is good to use a pan that you can put later in the oven. so if you have one with no plastic or rubber handle it would be perfect. If not you can later put the frittata in an oven suitable baking form.
When the olive oil is heated up add the zucchini and cook for 2 minutes. Right after that add the garlic, onion, and corn and cook for another 2 minutes. Season with salt and pepper.
Break the feta into chunks and spread over the veggies.
Mix the eggs with the cream and pour the mixture in the pan. Put the pan in preheated oven on 180 °C and bake for 10-15 minutes.