Cream the butter and sugar together until light and fluffy.
Grate in the zest of the lemon, add the ground cardamom and cream a bit more.
Beat in the eggs, one by one.
Sift in the dry ingredients, discarding any particularly large bits of bran left in the sieve and stir.
Juice the lemon and stir in gently with the grated marzipan until everything is just combined.
Gently stir in the cubed marzipan.
Spoon into twelve cupcake cases and bake at 180℃ (350℉, Gas 4) for about 20 minutes or until the cakes are golden and well risen.
Allow to cool for a couple of minutes, then turn out onto a wire rack to cool completely.
Adapted from Lemon & Marzipan Cupcakes by Ruby Tandoh.Please note: calories and other nutritional information are per serving. They're approximate and will depend on serving size and exact ingredients used.