Preheat oven to 450°. Separate eggs; place whites in a large bowl and yolks in 4 separate small bowls. Beat egg whites, Italian seasoning, salt and pepper until stiff peaks form.
In a 9-in. cast-iron skillet generously coated with cooking spray, drop egg white mixture into 4 mounds. With the back of a spoon, create a small well in the center of each mound. Sprinkle with cheese. Bake until light brown, about 5 minutes. Gently slip an egg yolk into each of the mounds. Bake until yolks are set, 3-5 minutes longer. Sprinkle with basil and tomatoes. Serve immediately.