In a large mixing bowl grate the almond paste with a large cheese grater. Add the baking powder, flour and lemon zest.
In another bowl add the egg whites and beat with an electric mixer while adding the sugar a little at a time until glossy and soft peaks form.
Fold the almond paste mixture into the egg whites until combined. Beat the mixture with the electric mixer until smooth, about 1 minute.
With a small ice cream scoop take a scoop of dough at a time and roll it into the pinoli nuts. Place the cookies on the prepared baking sheet about 2 inches apart. Bake for 15 minutes or until slightly golden. Transfer to a wire rack to cool.