This cake came into creation as the result of having some cooked sweet potato in the fridge that needed using up. I have been for years making a version of this cake using pumpkin after Halloween carving. I would turn it into a puree and make this cake, now I nearly always make it with sweet potato instead. I pop sweet potatoes into the oven and let them roast in their skins, which peels away easily when they are cooked and simply mash it into a puree with a fork. The cake has a simple icing that disappears as it sets and acts as a glue to stick the fragrant thyme to the cakes. The cake is sweet, moist and light with a subtle woodsiness from the thyme.