Cut the buttercup in dices and place on a baking tray. Sprinkle with olive oil, salt and pepper and cook in the oven until tender.
In the meantime, whisk together eggs, milk and greek yogurt
Cut the cheese into dices
Once the buttercup is cooked, remove the skin and puree with a fork or an electric mixer. Add the milk-yogurt mixture and combine well. Now add the flour, vanilla, chopped walnuts, nutmeg, salt and pepper. Finish by adding the cheese.
Pour the mixture in a cake pan and bake for about 30 min. Let cool before removong from the pan.