Mix the yeast with a little of the warm liquid and add the sugar. Allow the mixture to become frothy.
Mix the dry ingredients with the yeast liquid to make a batter.
Cover the batter with a clean cloth and leave in a dry place for an hour.
Bake the oatcake on a well-greased griddle or large frying pan.
Add enough batter to make an oatcake about 8-9 inches across. It will gradually become covered in holes as it cooks and the surface will change from wet and shiny to dull when it is ready to turn, after about 3 minutes. Turn the oatcake and cook for another 2-3 minutes.notes:These freeze well. Defrost them enough to unfold them then pop them under the grill.