• Preheat oven to Gas mark 4 / 180C.
• Line 2 large baking sheets with parchment paper.
• Beat together peanut butter and sugar in a large bowl with a mixer or spoon until smooth.
• Add beaten egg and bicarbonate of soda to peanut butter mixture and beat until well combined.
• Roll 1 teaspoon of dough into a ball and place on baking sheet.
• Place 12 balls onto each baking sheet and flatten gently.
• Bake for about 10 minutes until slightly puffed and a golden colour.
• Leave on the baking sheet for a couple of minutes and then place on a rack to cool.
• Store in an airtight container.

Variations

• Add any of the optional extras after beating the peanut butter and sugar and continue as above.