Preheat the oven to 350°F. Grease a muffin pan with coconut oil spray.

In a large bowl, whisk together the eggs, milk and 1/2 tsp of salt and pepper. Stir in the spinach, onions, mushrooms, pepper and herbs.

Divide the mixture evenly between the 6 muffin pan cups and bake the muffins for 20 to 25 minutes, or until the egg is fully cooked. Remove the muffins from the oven and let them cool for 5 minutes in the pan then use a knife to loosen the muffins from the cups.