1. Chop the onion. Slice the sausages into thin rings.

2. Heat 2 tablespoons olive oil in a skillet. Saute onion for about 1 minute, add the sausage slices, cook for 5 minutes or until golden brown.

3. Dice the tomato.

4. In a medium bowl, whisk together the eggs, all purpose flour and milk. Season the mixture with salt and pepper.

5. Preheat oven to 350 degrees F (175 degrees C). Grease one 8x8 inch (20x20 cm) casserole dish with 1 tablespoon olive oil.
6. Place the sausages and onions on the bottom of the casserole. Add layer of tomatoes.

7. Pour the eggs and milk mixture over the tomatoes.

8. Bake the omelet uncovered for 25-30 minutes, or until set in the center.