Strawberry Jam

Make Jam: Combine the chopped strawberries, granulated sugar, and orange juice in a medium saucepan. Cook over medium heat for about 10 minutes, stirring occasionally, until the strawberries have fully softened. Let the jam cool, then transfer to a jar and store in the fridge until ready to use. For a quicker option, store-bought jam can also be used.

Cake

Preheat: Preheat your oven to 350°F (175°C). Line the bottoms of two 6-inch cake pans with baking paper.

Zest orange: Reserve 1/4 cup of granulated sugar. In a large mixing bowl zest the orange into the remaining sugar and rub the zest into the sugar to release the orange flavor.

Cream butter and sugar: Add the softened butter and using an electric mixer beat the softened butter with the orange-sugar mixture until pale and fluffy.

Add egg yolks: Separate the egg yolks from the whites. Whisk the yolks with the sour cream and then add to the butter mixture, mixing until well combined.

Whisk egg whites: In a separate bowl, whisk the egg whites using an electric mixer with the reserved 1/4 cup of sugar until stiff peaks form.

Add dry ingredients: Sift the flour, baking powder, and salt into the batter and mix until just combined.

Fold in egg whites: Gently fold about one-third of the beaten egg whites into the batter until mostly incorporated but still streaky. Fold in the remaining egg whites until fully combined.

Prepare cake pans: Divide the batter evenly between the two prepared cake pans and smooth the tops.

Bake: Bake for about 30 minutes, or until a toothpick inserted into the center comes out clean. Let the cakes cool in the pans for 15 minutes before transferring to a cooling rack. Allow the cakes to cool completely before decorating.

Mascarpone Cream

Whisk together the mascarpone cream, crème fraîche (or sour cream), vanilla essence, and icing sugar until smooth and well combined.

To Assemble

Level the rounded top off one of the cakes to create the bottom layer.

Pipe or spoon a layer of mascarpone cream on top of the bottom cake layer. Optionally, pipe a border of cream around the edge.

Spread a layer of strawberry jam over the mascarpone cream and top with some sliced strawberries.

Place the second cake layer on top.

Frost the top of the cake with more mascarpone cream and decorate with additional strawberries.