In a medium skillet non-stick coated fry the finely chopped onion, peeled and cubed pumpkin and sage with olive oil until golden, about 10 minutes on medium heat. Eggs and the feta cheese mix in medium bowl. Put salt to taste and pour the mixture fry onion and pumpkin. Leave for 5 minutes on low heat, gently stirring until mixture begins to stiffen. Once frits tighten bottom, but the top is still liquid, bake a few minutes under the grill. Allow to cool for a few minutes and transferred to a plate. Can be cut into pieces still in the pan. For a stronger flavor can be added feta cheese, and can be of different types.