Heat a 10-inch pan over medium heat. Add the oil. Saute the leeks until soft. Add the squash, zucchini, and potatoes. Cook until the vegetables soften about 5 to 7 minutes.
In a bowl whip eggs and half and half; stir in ricotta. Add the Parmesan, a pinch of salt, and a grind of pepper. Brush a new pan lightly with oil and place over medium heat. Add the egg mixture, then tomatoes, followed by softened squash potato mix. Cook until the eggs are firm.
Recipe courtesy of Colin Ambrose