For the sheet cake
- unsalted butter 115g, at room temperature, plus extra for greasing
- virgin coconut oil 115g
- caster sugar 350g
- plain flour 420g
- baking powder 4 tsp
- fine sea salt 1 tsp
- vanilla extract 2 tsp
- coconut extract 2 tsp
- egg whites 5 large
- coconut milk 350ml
- desiccated coconut 85g
For the cream cheese icing
- unsalted butter 75g, at room temperature
- full-fat cream cheese 125g, at room temperature
- icing sugar 400g
- fine sea salt ¼ tsp
- vanilla extract 2 tsp
- desiccated coconut 60g, to decorate
Preheat the oven to 160C fan/gas mark 4. Lightly grease the baking tin and line with a strip of parchment paper that overhangs the two long sides, securing in place with metal clips.
For the cake, place the butter, coconut oil and caster sugar into a large bowl and, using an electric mixer, beat together on medium speed for 7-8 minutes, or until light and fluffy.
Meanwhile, mix together the flour, baking powder and salt in a separate bowl. Add the vanilla and coconut extracts to the butter mixture and mix briefly to combine, then add the egg whites, one at a time, mixing until fully combined before adding another. Add the flour mixture in three additions alternating with the coconut milk, starting and finishing with the flour. Fold in the desiccated coconut. Scrape the cake batter into the prepared tin and spread into an even layer. Bake for 35-40 minutes, or until the cake springs back to a light touch or a skewer inserted into the middle of the cake comes out clean.
Leave the cake to cool in the tin for about 15 minutes, before transferring it to a wire rack (using the parchment paper to lift it out) to cool completely.
For the icing, it’s very important that the butter and cream cheese are both at room temperature, otherwise it can be tricky to get the right texture. Place the butter and cream cheese in a large bowl and use an electric mixer to beat on medium-high speed for 2-3 minutes, or until smooth, creamy and fully combined. Add the icing sugar, salt and vanilla, and mix on slow speed until the sugar has combined with the butter mixture, then mix on medium-high speed for 4-5 minutes, or until light and fluffy.
Spread the icing all over the cooled cake, then sprinkle the desiccated coconut on top and serve.
This cake will keep for 2-3 days but, personally, I think it’s best eaten within a day of icing.