Pancake mix does not, contrary to popular belief, come from special bags labelled "Pancake mix" bought in the supermarket. It comes from mixing flour, eggs, melted butter, salt, milk, and optionally baking soda (the latter ingredient being the main difference between scandinavian and american pancakes). A good baseline is four eggs, a quart of milk, two cups of flour, two tablespoons of melted butter, a teaspoon of salt and a teaspoon of baking soda. Mix as you would any flour-based product - ie, start with the dry ingredients and mix the liquid into them - slowly, while stirring. Let the mix rest for at least 10 minutes before using - overnight for extra smooth.