Decadent Plum Cake

This cake sits somewhere between an afternoon treat and a "light" dessert. It's a decadent choice with a warm cup of tea and can also be dressed up with some softly whipped cream as the perfect post-dinner treat.
Ingredients
125g unsalted butter (softened), plus a little extra65g caster sugar
50g light brown sugar
2 large eggs
70g plain flour
70g wholemeal rye flour*
1 tspn baking powder
¼ tspn salt
2 tspn Sweet Spice
5 or 6 just-ripe plums, halved & pitted
85g cup sugar
- Pre-heat the oven to 180°C, and butter/flour/line an 8-inch square baking tin or a loaf tin.
- With electric beaters, beat the butter and both sugars until light, fluffy and pale. Add the eggs, beating well, and don't worry if the mixture looks a little curdled - it will come back together.
- Sift into the mixture both flours, the baking powder, salt and 1 tspn of Sweet Spice, and beat until just combined but try not to overmix.
- Spread the batter evenly in the tin, and top with the plum halves, cut side facing upwards. Combine the remaining 1 tspn of Sweet Spice and the sugar, and sprinkle over the plums. Dot with some thin slices of butter.
- Bake in the oven for 40-45 minutes or, turning halfway through so it browns & crisps evenly on the top.
- Allow to cool slightly before removing from the tin. This can be served warm or cold.
* if you can't find wholemeal rye flour, it's fine to double the plain flour