I created this GF cake because I liked the idea of lime & coconut together. It turned out very light and moist; an indulgent delight with a tropical breeze.
This recipe is wholly dairy-free if you use a suitable double cream substitute in the frosting.
For the cake:
- 280g gluten-free flour
- 130g caster sugar (golden or white)
- 5 tsp gluten-free baking powder (use 2 tsp if your GF flour is self-raising)
- 25g unsweetened desiccated coconut nibs, plus extra for garnish
- 6 large eggs, separated (they should total 360g-380g when weighed in their shells)
- 1 unwaxed lime, zest and juice
- 125ml (120g if weighing) vegetable oil
- 160ml (160g) water
- Butter, to grease tin (or dairy-free margarine)
For the coconut cream frosting and garnish:
- 1 unwaxed lime, zest and juice
- 225g raw coconut oil (see footnote)
- 100ml double cream, or suitable dairy-free alternative
- 2 tablespoons coconut rum (optional)
- 1 tablespoon vanilla extract
- 420g icing sugar – sift, if required, after measuring
- Unsweetened desiccated coconut nibs (see Cake Ingredients)
- 25g unsweetened coconut curls, to decorate
- A round, deep-sided cake tin 26cm (10″) or so in diameter
- Baking/parchment paper to line tin
- 3 large mixing bowls
- Electric mixer (hand-held or stand)
- Spatula and wooden spoon
- Oven-safe plate
- Cooling rack
- Preheat oven to 180 C (160 C fan-assisted). Grease your tin and line the bottom and sides with baking paper. Get 3 mixing bowls ready.
- In the first bowl, mix the flour, sugar, baking powder, and coconut nibs together with a fork.
- In the second bowl, whisk the egg whites to stiff peaks, starting at low speed and gradually increasing to high speed.
- In the third bowl, whisk the egg yolks with the lime juice, zest, oil, and water until doubled in volume and fluffy; again, start at low speed and gradually increase to high speed. (No need to clean the beaters from the whites.)
- Add the yolk mixture to the dry ingredients and fold together with a spatula until fully combined and smooth.
- Add one-third of the egg whites, folding briskly, to loosen the mixture. Then add the rest of the whites and fold carefully until no white lumps or streaks remain.
- Pour the batter into your prepared tin and smooth the top with the spatula. Bake in the oven for 20-25 minutes, turning halfway through for even baking, until a skewer inserted in the centre comes out clean. Cool the cake in the tin on a cooling rack (GF cakes can be too delicate to turn out of the tin while still hot).
Coconut cream frosting:
- When the cake has baked, turn the oven off. Spread the lime zest on an oven-safe plate, breaking up any clumps, and put in the oven – door ajar – for 30 minutes to dry out as the oven cools.
- Put the coconut oil into your mixing bowl, and break up any large lumps with your wooden spoon. Microwave on the defrost (or lowest) setting for 1 minute, then see if it’s pliable enough to beat as if you were creaming butter. If not, zap for 20 seconds more, and test again; continue until it’s softened enough.
- With the mixer on low speed, add about 3/4 of the double cream, the rum (if using), vanilla, and lime juice, one item at a time, to the softened coconut oil, whisking after each addition. Scrape down the bowl really well, and whisk 1 minute on medium speed.
- Add the icing sugar gradually, whisking continuously on low speed. Once all in, scrape down the bowl again and continue whisking on medium speed about 2 minutes.
- If the mixture is too stiff for you, add the rest of the cream 1 tablespoon at a time, whisking at medium speed for about 30 seconds after each addition, until you have the consistency you want.
- Slice the cooled cake in half horizontally. Spread about 1/4 of the frosting over the bottom layer, then sprinkle some coconut nibs and dried lime zest over. Put on the top cake layer, and spread the rest of the frosting over the top and sides. Sprinkle over more coconut nibs, then the remaining dried lime zest, then the coconut curls to garnish.
Raw coconut oil is sold as a solid (in a jar) in most supermarkets. When baked, it doesn’t have a strong coconut taste, and it’s lactose-free so it’s excellent for someone avoiding butter. However, you can use unsalted butter in the frosting if you prefer (which is the original recipe from The Kitchn which I adapted); you’ll need to add coconut flavouring, though.
Layer Cake Tips
I’m hopeless at slicing cakes in half horizontally, so when making a layer cake, I bake the layers separately. After pouring the cake mix into the tins, I use the spatula to create a slight depression in the centre of one of the cakes – this helps to make a flatter rise for the one that becomes the base layer.