Here goes.
225g GF self raising flour
Quarter teaspoon of xanthan gum (optional but stops it crumbling as much)
Half teaspoon of salt
1 teaspoon of Colemans mustard powder (I checked it's GF)
125g grated mature cheese
1 beaten egg
2 tablespoons melted butter
150ml milk
Optional extra 2 tablespoons chopped fresh chives.
Will fit either 23cm square cake tin or 2 Victoria sandwich tins- grease and line base with baking paper.
Preheat oven to 190/375/Gas 5.
Sift dry ingredients into a large mixing bowl
Set aside 3 tablespoons of cheese, stir the rest into the dry mix.
Add the milk, egg and butter to the mix and stir thoroughly. You may need a little more milk as GF flour seems to be thirsty! Consistency of my mix is usually like thick egg mayo.
Spread mix evenly into cake tin and sprinkle remaining cheese on top.
Bake for 25-30 minutes. Cut into portions with pizza cutter before removing from tin, may need palette knife to lift from paper. Burn mouth on first bit. Cool rest on wire rack, slapping rest of family's hands away 