Store-bought Sponge with Lemon Curd, Blueberries and Almonds

Have 2 x 1½ cup-capacity sterilised jars at the ready.

Lemon curd: Heat the sugar, butter and zest in the top of a double boiler, or in a large glass bowl set over a saucepan of simmering water. Whisk the lemon juice and cornflour together and whisk into the butter mixture. Whisk the eggs together separately then whisk into the butter lemon mixture. Continue whisking over the heat for 8-10 minutes, until the mixture has thickened enough to coat the back of a wooden spoon; don’t keep waiting for it to get really thick or it will start getting cooked-eggy. Pour into jars and seal. Cool and use within 2 weeks. Makes about 2½ cups

Citrus sugar syrup: Whisk the sugar, water and lemon juice together in a saucepan. Bring to a boil, whisking until the sugar is dissolved, then add the zest. Reduce the heat to a simmer and cook for 8 minutes. Remove from the heat and whisk in the Limoncello. Cool and store in a covered container in the fridge for up to a week. Makes ¾ cup

Cream topping: Whip the cream to soft peaks then beat in the sour cream. Sift in the icing sugar and lemon zest and beat again briefly to combine.

To assemble: Place one sponge cake on a serving plate and brush with ¼ cup of the citrus sugar syrup. This requires patience as it will take a few minutes to absorb before you can continue with more syrup. Top with ¼ cup of the lemon curd and ½ of the cream topping. Repeat with the remaining sponge layer, finishing with curd, cream, a sprinkling of slivered almonds and blueberries (first toss them through the remaining citrus sugar syrup and drain in a sieve).