Place the turkey sausage in a large skillet and cook until browned and cooked through. Transfer to a paper towel to drain.
Heat olive oil in a large skillet set over medium heat. Add the mushrooms and black pepper and cook, stirring occasionally, until the mushrooms are tender, about 5 minutes. Season with salt.
Add the cooked sausage and the tomatoes to the mushrooms.
Coat four 6-ounce ramekins with nonstick cooking spray or grease with butter. Divide the mushroom mixture between the ramekins.
In a large bowl, whisk together eggs, egg whites and water. Divide the mixture between the ramekins, pouring over the mushroom mixture. Divide the basil evenly between the ramekins.
Place the ramekins on a baking sheet and place in the oven. Cook until the eggs are set, about 20 minutes. A few minutes before the cooking is done, sprinkle the eggs with Parmesan and place back into the oven.
Remove from the oven, transfer the ramekins to plates and serve immediately.
Make-ahead: The night before, you can make the mushroom, bacon and tomato mixture and prepare the egg mixture. Place the mushroom mixture in the prepared ramekins. Cover and chill the ramekins and the egg mixture. In the morning, pour the egg mixture over the mushrooms, sprinkle with the basil and bake as directed.