Bicarbonate of Soda - 200g. Use as a raising agent for baking, such as gingerbread, parkin and soda bread. Combine with cream of tartar to make your own baking powder in a ratio of 1 part bicarb : 2 parts cream of tartar.
Has many other uses around the house, for cleaning and deodorising, e.g. the fridge and freezer.