Grantham gingerbread arose as a result of a 'mistake', an event that seemingly occurs all too often in the invention of British sweets and puddings. A local baker in the 1740's was making Grantham Whetstones, a flat hard biscuit for travellers. He mistook one ingredient for another and the result became Grantham Gingerbread.
Cream the sugar and butter together. Beat in the egg. Sift the flour, bicarbonate of soda, baking powder and ground ginger together. Fold into the creamed mixture.
Make into small balls or drop by teaspoon onto an ungreased baking sheet.
Bake at 150 °C / 300 °F / Gas 2 for 20 minutes or until light brown.