Leftovers Frittata - great for using up the end of that bag of spinach and the half block of feta you've forgotten why you bought. Soften half an onion. Whilst spinach in a large pan. Whisk together your eggs with some milk and grated cheese (Parmesan is best, but cheddar for less intense taste works). Pour egg mix into pan and stir to distribute spinach. Wait until bubbling on top and add cubed feta. I then transfer to under a hot grill, but you can flip if you choose. Serve with a light salad.