Preheat your oven to 350°F (175°C) and grease a standard 12-cup muffin pan.

In a large mixing bowl, whisk together the eggs and milk until frothy, then add salt, pepper, and herbs.

Prepare the spinach and feta by chopping fresh spinach (or thawing frozen) and mixing them into the egg mixture.

Carefully pour the egg mixture into the prepared muffin pan, filling each cup about three-quarters full.

Bake for 18-20 minutes until puffed and edges are lightly golden. Centers should be set and slightly springy.

Let the muffins cool for 5 minutes, then run a knife around the edges to loosen and remove from the pan.

Serve warm or at room temperature, perfect for breakfast or snacks.