In a 12-inch non-stick, oven proof skillet, heat 1 teaspoon of the oil over medium high heat and cook sausage, green onions and garlic, breaking up with a spoon, for 3 minutes. Stir in apple, fennel (if using) and nutmeg; cook, stirring for about 4 minutes or until sausage is no longer pink and apples are tender crisp. Scrape into a bowl; set aside.
Return skillet to medium low heat and add remaining 1 teaspoon oil.
In a separate bowl, whisk together eggs, water and pepper. Pour into skillet and cook, stirring gently until eggs start to set. Place under the broiler for 3 minutes or until eggs are completely set and puffed. Slide the omelette onto a serving platter and spread sausage mixture on half of the omelette. Fold remaining half over sausage filling to cover.
You can find bulk sausage meat in most butcher and grocery stores. You can use 8 ounces instead of 2 sausages.
To make your skillet ovenproof if the handle is wood or metal, wrap it in foil before using.
Leave the skin on the apple for additional fibre and colour.