Marmalade Drizzle Cake

What to do:

Line a 20cm square cake tin with greaseproof paper and butter the paper. Set oven to 180C/Gas 4.
Cream the butter and sugar together until light.
Slowly beat in the eggs, (if you add a little flour at the end it will prevent curdling).
Add in the lime zest, the flour and almonds.
Fold in about 3 tablespoons of lime juice, the mixture should drop easily from the spoon when tapped.
Fold in three quarters of the blueberries and raspberries and pour into the cake tin.
Smooth the surface with a pallet knife, then scatter the remaining fruit on top, it will sink as the cake rises.
Bake for about 1 hour (cover with foil if beginning to brown too much), or until firm to a gentle prod in the centre. When you put in a skewer it should come out clean.
Meanwhile make the drizzle: Put the lime juice, Bay Tree Seville Orange Marmalade, lime zest and 60g sugar in a small saucepan over a low heat. Stir regularly until it all dissolves together, without allowing to bubble. You can add more sugar at this stage if you think it's too sharp - but be careful the drizzle may be hot!
As soon as the cake comes out of the oven, prick all over with a skewer then spoon the drizzle over it.
When cool, carefully remove the cake from the tin, discard the lining paper and cut into 12 pieces.