Preheat oven to 350°F. In a large bowl, whisk together eggs, egg whites, milk, dill, pepper, and salt.
Reserve 1/4 cup each of the cheese and ham, and 1 tablespoon of the dried tomatoes. Add spinach and remaining cheese, ham, and tomatoes to the egg mixture. Stir well.
Coat a 12-inch oven-safe nonstick skillet with cooking spray. Heat skillet over medium heat. Add egg mixture and cook, without stirring, until edges are set, about 5 minutes. Sprinkle the reserved cheese, ham, and tomatoes on the top. Transfer to the oven and bake until eggs are cooked through and the cheese has melted, about 16 minutes. Transfer to a serving platter. Slice into pizza-style triangles. Serve warm, or at room temperature.