In a non stick pan over medium heat, add the olive oil and sauté the zucchini and the chorizo, for about 5 minutes.
In a bowl, beat the eggs and add 1 ½ cups of cheese and ¾ cup of green onions.
Season with salt and pepper to taste.
Add the sautéed zucchini and chorizo to the egg mixture. In the same pan, over low heat cook the frittata, covered, for 8 minutes.
With a spatula lift cooked edges and flip the frittata on to a plate, a bit bigger than the pan, and then slowly slide the frittata back to the pan.
Cook until done, approximately 6 more minutes.
Sprinkle the rest of the cheddar cheese on top, and broil the frittata in the same pan for 3-5 minutes until the cheese melts.
Garnish with the rest of the green onions.