A post by Brown Butter Book

Ingredients

• For the sponge: 200 g unsalted butter, softened
• 200 g caster sugar
• 4 large eggs (about 200 g without shells), at room temperature
• 200 g plain flour
• 8 g baking powder
• 2 g fine salt
• 30 g whole milk
• 8 g finely grated lemon zest
• For the filling: 250 g mascarpone, cold
• 150 g double cream, cold
• 35 g icing sugar
• 10 g lemon juice
• For the amber citrus sauce: 100 g caster sugar
• 30 g water
• 80 g lemon juice
• 40 g unsalted butter, cubed
• For serving: 100 g double cream, whipped to soft peaks
• 4 strawberries, halved lengthwise

Let’s make it

1. Heat the oven to 175°C conventional (160°C fan). Grease and line the base of a 20 cm round cake tin, 5 cm deep.
2. Beat the butter, sugar and lemon zest until pale and fluffy, about 3 minutes. Beat in the eggs one at a time, scraping the bowl between additions. If the mixture looks curdled, beat in a spoonful of the measured flour.
3. Whisk together the flour, baking powder and salt. Fold into the butter mixture in two additions, alternating with the milk, just until no dry streaks remain. Scrape into the tin and level the top.
4. Bake for 28–33 minutes, until golden and a skewer inserted in the centre comes out clean. Cool in the tin for 10 minutes, then turn out and cool completely on a rack, about 45 minutes.
5. For the sauce, put the sugar and water in a small saucepan and heat over medium heat without stirring until the syrup turns deep amber. Remove from the heat and carefully whisk in the lemon juice; it will bubble vigorously. Return to low heat and stir until smooth, then whisk in the butter. Cool until thick but still pourable, about 20 minutes.
6. Beat the mascarpone, cream and icing sugar just until smooth and thick, then mix in the lemon juice. Avoid overbeating. Slice the cooled sponge horizontally into three even layers with a long serrated knife.
7. Set the bottom layer on a serving plate. Spread over half the filling in a thin, even layer, add the middle sponge, then spread on the remaining filling and top with the final sponge layer. Chill for 30 minutes to help the filling settle.
8. To serve, cut the cake into 8 wedges. Place a generous wedge on each plate, spoon soft whipped cream over the center, drizzle with the cooled amber citrus sauce and add a strawberry half alongside. Keep the remaining cake covered and refrigerated.

Kitchen notes

This is an AI-assisted recipe in development and has not been kitchen-tested; the photo is decorating inspiration rather than the tested result. Contains wheat, eggs and dairy. Store covered in the refrigerator for up to 3 days; keep the sauce chilled separately and warm it gently until pourable before serving.

Recipe in development · not kitchen-tested.