For the cake:
225g butter at room temperature
200g caster sugar, plus 2 tablespoons extra to sprinkle
2 small sprigs of rosemary (about 1 teaspoon once finely chopped)
3 large eggs, lightly beaten together
275g plain flour
1½ teaspoons baking powder
100g Mrs Bridges Pink Grapefruit Marmalade, roughly chopped
2 tablespoons poppy seeds
For the icing:
75g Mrs Bridges Pink Grapefruit Marmalade
100g icing sugar
Preheat the oven to 160°C Fan. Butter and line a 2LB loaf tin. To do this cut a strip of baking parchment that lines the bottom of the tin and comes up the short sides of the tin and slightly overhangs, this will allow you to easily lift the cake out once it is baked.
Put the butter, sugar and finely chopped rosemary in the bowl of a stand mixer with the beater attachment and beat for a minute or two, until well combined but not too fluffy. This is an unctuous loaf cake, not a super light sponge, so you aren’t trying to incorporate too much air. If you aren’t using a stand mixer then put in a large bowl and mix by hand or with an electric mixer.
Weigh the flour and baking powder into a large bowl and use a whisk to combine them and gently break up any clumps. Add one of the eggs to the butter and sugar mixture with a tablespoon of the flour mixture and beat to combine – repeat with the other two eggs adding a tablespoon of the flour mixture each time.
Add the rest of the flour and gently fold it into the batter. If you are using a stand mixer, a couple of rotations of the beater and then gently using a spatula to combine the last floury bits is perfect. Add the Mrs Bridges Pink Grapefruit Marmalade and poppy seeds and gently mix again, be careful not to overmix the batter.
Put the batter in the prepared loaf tin and smooth the top. Sprinkle over a couple of tablespoons of caster sugar. Put in the oven and bake for 45-55 minutes. You will know it is ready when a skewer comes out clean. Once cool enough to handle remove it from the loaf tin to a cooling rack.
Allow to cool completely before icing. To make the icing sieve the Mrs Bridges Pink Grapefruit Marmalade to remove any rind. If this is tricky to do warm the marmalade first for a minute or two in a small pan or a microwave. Mix some of the sieved marmalade with the icing sugar until a thick icing forms – you can add a drop of water if needed. Spread the icing over the cooled loaf cake, allowing a little to drip down the sides if you like. Use the reserved rind from the marmalade or a couple of slices of fresh pink grapefruit to decorate.