Prepare the bowl. Lightly coat the inside of a microwave-safe cereal-sized bowl with Pam cooking spray to help prevent sticking.
Prepare the spinach. Wash the spinach leaves, pat them dry, remove any tough stems, and tear them into bite-sized pieces. Spread the spinach across the bottom of the prepared bowl.
Add the vegetables and bacon. Slice or dice the Roma tomato and add it over the spinach. Chop the turkey bacon into small pieces and distribute it evenly over the vegetables. Use fully cooked, ready-to-eat bacon, or cook it separately first.
Add the cheese. Sprinkle the shredded mozzarella over the spinach, tomato, and bacon mixture.
Mix the eggs. In a separate cup or small bowl, lightly beat the eggs with the evaporated milk using a fork until combined.
Combine everything. Pour the egg mixture over the vegetables, bacon, and cheese. Some ingredients may float toward the surface, which is normal. Season lightly with salt and pepper.
Microwave the frittata. Place the bowl in the microwave and cook on high for approximately 3 minutes. Cooking time will vary depending on microwave wattage. Watch for the center to puff up to approximately the same height as the edges. The original method suggests cooking for about 20 seconds longer after this happens.
Check for doneness. Make sure the eggs are fully set, with no liquid egg remaining. For food safety, egg dishes should reach an internal temperature of 160°F (71°C). If additional cooking is needed, microwave in short intervals until done.
Serve immediately. Carefully remove the hot bowl from the microwave. Enjoy the frittata while it's warm and fluffy, as it will gradually deflate and become firmer as it cools