1. Cut the stems off the spinach, chop the leaves coarsely and then wash very well in water a few times to remove all sand. Drain well.
2. Heat the oil or butter in a very large saute pan over moderate heat. Add the onion and cook a few minutes.
3. Add the garlic and spinach leaves to the pan, stirring often until the spinach wilts.
4. Add the mint, mix well, and season to taste with salt and pepper. Top with chopped walnuts.
As a salad variation, chill the cooked spinach mixture and fold in the yogurt after the mixture is cold. Top with the chopped walnuts and mint.Serving Size: about 1/2 cup