Step 1: Preheat the oven

Preheat your oven to 180°C (350°F). Line a baking tray with parchment paper.

Step 2: Cream butter, peanut butter, and sugar

In a mixing bowl, cream together the softened butter, peanut butter, and caster sugar until light and fluffy.

Step 3: Add the egg

Beat in the egg until fully incorporated.

Step 4: Combine dry ingredients

In a separate bowl, sift together the plain flour, baking powder, and salt. Gradually add the dry ingredients to the wet mixture, mixing until a dough forms. Fold in any optional add-ins, like chocolate chips or chopped peanuts.

Step 5: Shape the biscuits

Scoop small portions of the dough (about 1 tablespoon each) and roll them into balls. Place the balls onto the prepared baking tray, spacing them 2 inches apart. Flatten each ball slightly with a fork, creating a crisscross pattern.

Step 6: Bake

Bake in the preheated oven for 12-15 minutes, or until the edges are golden and the biscuits are slightly firm to the touch. Allow them to cool on the tray for 5 minutes before transferring to a wire rack.