1Preheat oven to moderate, 180 C. Line 2 oven trays with baking paper.
2In a bowl using an electric mixer, beat butter, peanut butter and sugar together until smooth and creamy. Add egg, beating until just combined. Stir in combined sifted flour and soda.
3Roll level tablespoons of mixture into balls. Arrange on trays 5 cm apart and press in a lightly floured finger to make an indentation in the centre of each cookie. Flatten slightly using floured fingertips. Spoon about ½ tsp jam into centre of each cookie (should be just level with top of cookie).
4Bake 12 to 15 mins until golden. Cool completely on trays. Store in an airtight container.