5 plums, stones removed, quartered, then cut in half again
2 tbsp demerara sugar
8 sprigs of thyme
225g unsalted butter (at room temperature)
225g golden caster sugar
3 large free-range eggs, beaten lightly
125g ground almonds
200g orange with whisky marmalade
1 tsp almond essence (optional)
Zest from 1 large orange
100g plain flour
1 tsp baking powder
Pinch of sea salt flakes
3 tbsp orange with whisky marmalade
Preheat the oven to 160 C (conventional)/140 C fan.
Butter a 20 cm springform cake tin (the tall kind) and line the base with parchment paper.
Sprinkle the demerara sugar over the plums. Add the leaves from half of the thyme sprigs.
Beat together the butter and sugar until pale and fluffy.
Gradually add the eggs, beating between each addition. Add a tablespoon of the weighed flour if the mix looks like it might curdle.
Gently fold the almonds, marmalade, almond essence, orange zest, flour, polenta, baking powder, and sea salt into the mix using a spatula or metal spoon.
Spoon the batter into the prepared tin. Top with the plums.
Bake for 1 h 30 min (you may need to cover the cake after 1 hour 15 mins to prevent it from browning too much).
Place the rest of the marmalade in a small pan with 2 tablespoons of water, and bring to a simmer on a medium heat. Pass the marmalade through a sieve and use to glaze the cake.