Place the sliced strawberries, sugar, lemon juice, and zest into a saucepan and massage the sugar and juice into the strawberries with your hands until well combined. Leave to sit until the natural juices have been released, about 1 hour.

Put the saucepan over medium heat and bring to a simmer. Cook for 20 minutes, stirring occasionally, or until the jam is at a consistency you like. For a smoother jam, use a potato masher to mash up the strawberries.

You will not need all of the jam for this recipe. Store the remainder in a sterilised jar, and keep in the fridge for up to 14 days.

Preheat the oven to 355°F (180°C). Grease two 6-inch baking tins, and line their bases with parchment paper if desired.

Dump the eggs and sugar into the bowl of a stand mixer fitted with the whisk attachment and beat on high until doubled in size and pale in colour, about 10 minutes.

Add the sifted flour and baking powder in thirds and gently fold it in with a spatula. Be sure there are no lumps of unincorporated flour. Pour the melted and cooled butter to the batter and carefully fold it in, being careful not to overmix.

Divide the batter between the two prepared tins and bake them for 15-16 minutes, or until a toothpick inserted into the centre of each sponge comes out clean.

Remove the tins from the oven and leave them to cool for 5 minutes. Turn out the sponges from the tins and let them cool completely on a wire rack, or at least 20 minutes.

Whisk together the heavy cream and sifted icing sugar on medium-high speed until the cream holds stiff peaks. Be careful not to overmix, or the cream will look dry.

Place one of the cakes flat side up on a serving plate. Spread half of the whipped cream on top of the cake, then spread the homemade strawberry jam on top. Carefully place the other cake flat side up over the jam and spread the remaining cream on it. Garnish with fresh strawberries and a generous dusting of icing sugar. Slice and enjoy immediately!