Heat the oven to 180C/160C fan/gas 4. Beat the butter with both types of sugar and the salt. Beat in the egg, vanilla extract and mincemeat. Stir in the flour and bicarbonate of soda, then chill for 20 mins.

Scoop tablespoons of the mixture onto two lined baking sheets, leaving a bit of space between each so they can spread. Bake for 10-12 mins, or until the cookies are just firm around the edges but still soft in the middle – they will firm up as they cool. Transfer to a wire rack and leave to cool.