Zucchini Lime Cake with Lime Cream Cheese Frosting
Zucchini in a cake might sound like a stretch, but stay with me. It keeps the crumb incredibly moist, it completely disappears into the batter, and paired with a generous amount of lime it makes for one of the most refreshing cakes I’ve made in a long time. This Zucchini Lime Cake with Lime Cream Cheese Frosting is bright, beautiful and the kind of thing that gets people asking for the recipe.
Three things that will make this cake: rub your lime zest into the sugar before you do anything else, it releases the oils and gives you a much brighter citrus flavour throughout. Use block cream cheese for the frosting, not the spreadable kind, or it will be too soft to work with. Don’t skip souring your milk, this help keeps the cake moist!
Makes a two-layer 18 cm (7-inch) cake · Serves 10–12
Ingredients
Cake
250 g full-cream milk
Juice of 1 lemon
300 g plain flour
1 tsp bicarbonate of soda
1 tsp baking powder
½ tsp salt
300 g caster sugar
Zest of 2 limes, plus the juice of 1
115 g unsalted butter, at room temperature
2 eggs, at room temperature
1 tsp vanilla extract
200 g zucchini, coarsely grated
Lime cream cheese frosting
125 g unsalted butter, at room temperature
150 g icing sugar, sifted
250 g block cream cheese, cold from the fridge
Zest of 2 limes, plus extra to decorate
A pinch of salt
1–2 tsp lime juice
Method
Cake
Prep. Preheat the oven to 180°C (160°C fan). Grease two 18 cm round cake tins (at least 5 cm deep) and line the bases with baking paper.
Sour the milk. Stir the lemon juice into the milk and set aside for 10 minutes until it thickens and curdles slightly.
Mix the dry ingredients. Whisk together the flour, bicarb, baking powder and salt.
Cream the butter and sugar. Rub the lime zest into the sugar with your fingertips until fragrant. Add the butter and beat for 3–4 minutes until pale and fluffy. Beat in the eggs one at a time, then the vanilla.
Combine. Add all the soured milk and all the dry ingredients at once and mix on low speed until just combined. Add the zucchini and lime juice and fold through to finish.
Bake. Divide the batter evenly between the tins and bake for 35–40 minutes, until golden and a skewer inserted in the centre comes out clean.
Cool. Cool in the tins for 10 minutes, then turn out onto a wire rack to cool completely.
Frosting
Beat the butter until pale and creamy, about 2–3 minutes. Add the icing sugar gradually on low speed, then beat on medium until light and fluffy.
Add the cold cream cheese, lime zest and salt, and beat for 30–60 seconds until smooth. Don’t overbeat. Add lime juice to taste, a little at a time. If the frosting feels soft, chill it for 15–20 minutes before using.
Assemble
Level the cooled cakes with a serrated knife if needed. Place one layer on a cake stand or board and spread over about a third of the frosting. Top with the second layer, cut side down.
Finish with the remaining frosting. I use a large basket weave nozzle to pipe the finished look, but you can simply spread it with a knife and create any pattern you like. Decorate with extra lime zest.
Notes
I keep the icing sugar low because it lets the lime really shine, but you can increase it if you prefer a sweeter frosting.
Rubbing the zest into the sugar releases the citrus oils and gives a much brighter flavour.
If your tins are shallower than 5 cm, put a tray underneath while baking in case of overflow.
If you don’t have lemon for the milk, 1 tbsp of white vinegar will sour it just as well.
Use block cream cheese rather than spreadable tub cream cheese, which is too soft and will make the frosting runny.
The cake layers can be baked a day ahead, wrapped well and kept at room temperature. Once frosted, store the cake in the fridge and bring it to room temperature for 30 minutes before serving.