Cream butter, vanilla, lemon rind, sugar & peanut butter together.
Work in flour & bicarb soda to make a stiff dough.
Roll heaped teaspoonfulls into small balls with floured hands & place on greased oven tray.
Press bisuits down lightly with a fork for crinkle effect. (NB: I forgot this step)
Bake at 180°C for about 15 mins. When it comes out of the oven the cookies will most likely feel really soft, and will fall apart if you pick them up. It's best to let them cool thorougly first.