Add oil to an oven-safe pan or skillet (like a cast iron skillet) over medium-high heat on the stove. Most common cooking oils like olive oil or avocado oil are perfect.
Add diced ham to the skillet. This can be store bought ham or leftover ham from Christmas or Sunday lunch.
Next, add in a little bit of butter. The butter will enhance the flavour, and also keep the meat from sticking to the pan, along with the oil.
Add in some kale to the skillet. The kale should be freshly washed with the stems removed so that it's easier to eat.
Toss in a few diced tomatoes. I like to use cherry tomatoes but really any kind will do! Even with the tomatoes, this keto frittata comes to just 2.7g net carbs per serving!
Stir the ingredients to help the kale to wilt a little, and the tomatoes to break down just a bit.
Sprinkle in some cheese over the ingredients, spreading it out evenly. I like to use a sharp mature cheddar, but your favourite hard cheese is fine!
In a separate bowl, whisk together eggs, milk or cream, and pepper, as if you're about to make scrambled eggs.
Quickly, pour the egg mixture over the other ingredients in the skillet or pan and then...
Carefully tilt the pan so that the egg mixture spreads evenly throughout all of the ingredients.
Bake and then dig in! This Ham and Cheese Frittata recipe is perfect for breakfast, brunch, lunch or even dinner!