Preheat the oven to 350 degrees F (180 degrees C). Coat a 9-inch cast iron skillet with Nonstick Cooking Spray (to taste). Set aside.
In a deep 12-inch cast-iron skillet, fry the Bacon (1 pound) over medium-high heat until crisp (you may need to do this in several batches). Remove to paper towels to drain.
Pour all the bacon fat out of the skillet except 1 tablespoon. Add the Fresh Baby Spinach (4 ounce) and Cherry Tomato (1/4 cup) and cook over medium heat, stirring a few times, until the spinach wilts and the tomatoes heat through.
In a large bowl, scramble the Egg (15) and season with Kosher Salt (1 tablespoon) and Ground Black Pepper (1 teaspoon). Pour into prepared skillet.
Transfer the spinach and tomatoes to the prepared skillet. Evenly sprinkle the grated White Cheddar Cheese (2 cup) over the top. Crumble the bacon and sprinkle over the cheese.
Bake the frittata until the center is set, 25 to 30 minutes. Let rest on top of the stove before cutting into wedges to serve.