Preheat your oven to 375 F.
Whisk together eggs and milk. Add diced tomatoes and cheese and mix evenly.
Pour mixture into muffin tins (use either lightly greased tins or line the muffin pan with muffin liners).
Bake for 17-20 minutes or until a fork comes out clean. Serve immediately or store leftovers in refrigerator for up to 1 week.