Preheat oven to 180C/350F/Gas 4. Line two cookie sheets with parchment paper and set aside.

Using an electric mixer or a wooden spoon, beat together the peanut butter, butter, white sugar, brown sugar, vanilla, and egg until just combined.

Add the flour, baking soda, and baking powder and beat together to form a dough.

Roll heaped tablespoons of dough into 1¼"/3cm balls and place on prepared cookie sheet about 3"/7.5cm apart as they will spread during cooking.

Use a fork to create a criss-cross pattern on top of each ball of dough, pressing to flatten slightly.

Bake for 10-15 minutes until golden.

Leave to cool for 5 minutes on the cookie sheet before transferring to a wire rack to cool completely