Preheat oven to broil. In a small bowl, whisk together eggs, milk, thyme, and salt. Melt butter in 10-inch oven-safe skillet over medium heat. Add spinach and sauté until just wilted, about 1 minute. Whisk TABASCO® Sauce into egg mixture, lower heat to medium-low, and pour in eggs. Cook for 2 minutes, stir, and continue cooking until bottom is set, about 2 more minutes. Sprinkle the top with chopped tomato and cheese.
Place skillet under the broiler and cook until frittata is golden, 5 minutes. Let sit for 5 minutes and serve.
Makes 4 servings.