I'm not going to give you the complete recipe; just a hint of the alchemy. If it sounds to your taste, then Google will provide the exact details.
Sussex Pond is classic 'nursery food'. A steamed suet crust pastry, filled with a whole multi-pierced lemon, butter, and sugar, then steam-cooked for 3 or 4 hrs. The stock-photo I've used doesn't really do it justice.
Amazingly (for a good Sussex boy) I've only ever eaten this ONCE. My friend Terry (an honorary Sussex-girl) cooked it for me, almost by cohersion. We all agreed that it was overly SWEET, so if the idea appeals try making it with about HALF the recommended amount of sugar.
N.B. This 'half the sugar' business applies to jam-making and almost everything else you can think of. Everything tastes so much better less sweet! When I was first married, the authoritarian Lady Magnon insisted that I stop lacing my tea and coffee with sugar; I have since been eternally grateful.