I made a really quick lemon cake today using rice flour instead of wheat flour. I didn't measure the ingredients but just put them together until they amounts looked right!
I took about 125g margarine and mixed with sugar. Then I added rice flour, 1 flat tsp baking powder and 1 heaped tsp of bicarbonate of soda. I then added 2 tbs of white vinegar, 1 tsp of lemon essence and mixed well. I added soya milk until it made a fairly wet mixture. I put into a greased oven dish at 180 until a knife came out clean. Then I cut into rectangle shapes and left to cool for about 15 mins until serving. It was lovely with some soya cream poured on.