Raspberry Jam-Filled Lamington Squares

Bake the Vanilla Sponge Cake

1. 1Preheat your oven to 180°C (350°F). Grease and flour a 20x30 cm (8x12 inch) baking pan, or line it with parchment paper.
2. 2In a large bowl, whisk together the sifted flour, sugar, baking powder, and salt.
3. 3Add the softened butter to the dry ingredients and mix until the mixture resembles coarse crumbs.
4. 4In a separate bowl, whisk together the eggs, vanilla extract, and milk.
5. 5Gradually add the wet ingredients to the dry ingredients, mixing until just combined. Be careful not to overmix.
6. 6Pour the batter into the prepared baking pan and spread evenly.
7. 7Bake for 30-35 minutes, or until a wooden skewer inserted into the center comes out clean.
8. 8Let the cake cool in the pan for 10 minutes, then invert it onto a wire rack to cool completely before slicing.

Assemble the Lamingtons

1. 1Once the cake is completely cool, carefully slice it horizontally into two equal layers using a long serrated knife.
2. 2Place the bottom layer of cake on a serving platter or clean cutting board.
3. 3Spread the raspberry jam evenly over the bottom layer of cake.
4. 4Whip the heavy cream (with powdered sugar, if using) until stiff peaks form. Spread the whipped cream over the jam layer.
5. 5Carefully place the top layer of cake over the whipped cream.
6. 6Chill the assembled cake in the refrigerator for at least 30 minutes to firm up, making it easier to cut.
7. 7Cut the chilled cake into 12 equal squares (approximately 6x7.5 cm or 2.5x3 inches).

Prepare Chocolate Icing and Coat the Lamingtons

1. 1Gently melt the chopped dark chocolate and butter together in a heatproof bowl set over a pan of simmering water (bain-marie), stirring until smooth.
2. 2Alternatively, microwave the chocolate and butter in 30-second intervals, stirring in between, until melted and smooth.
3. 3Allow the chocolate icing to cool slightly until it thickens enough to coat but is still pourable. You want a consistency that will coat the cake without being too runny.
4. 4Place the toasted desiccated coconut on a shallow plate or in a wide bowl.
5. 5Working with one lamington square at a time, dip each side into the chocolate icing, allowing excess to drip off.
6. 6Immediately roll the iced lamington in the desiccated coconut, ensuring it is coated on all sides. Place on a wire rack set over parchment paper to catch drips.
7. 7Repeat with the remaining lamington squares. Let the icing set at room temperature or briefly in the refrigerator.