Place the baby spinach into a sieve or colander over the top of a large bowl or sink. Pour boiling water over the spinach until it wilts. Leave for 5 minutes.
Carefully squeeze out the excess liquid from the spinach and set aside.
Sift the self raising flour into a large bowl. Add the dried herbs, strained spinach, halfof the feta cheese, half of the grated cheese and the chopped sun-dried tomatoes. Season with salt and pepper. Mix to combine.
In a separate bowl, whisk together the milk, sour cream, melted butter and eggs. Pour the liquid into the well in the dry ingredients. Gently mix to combine.
Divide the mixture equally between the muffin cases. Sprinkle the remaining feta and grated cheddar cheese over the top. Bake in the oven for approximately 20 minutes.