- Preheat oven to 350˚F (use regular heat, not convection). Grease 2, 8” round cake tins with butter. Cut a circle of parchment paper to fit the bottom of each pan.
- Place flour, baking soda, baking powder and salt in a bowl and whisk to combine.
- Place dipping wafers and warm water in a small pot. Set over low heat and stir until chocolate is melted. Remove from heat and set aside.
- Place 1 cup butter and 1 1/2 cups sugar in the bowl of your stand mixer fitted with the paddle attachment. Beat until well blended. Now beat in eggs, one at a time. Mix in the flour mixture alternately with buttermilk. Scrape down the sides of the bowl and mix again.
- With the machine running, slowly mix in the melted white chocolate mixture, ensuring all of it gets into the bowl. Divide the batter between the two cake pans. Bake the cakes in the middle of the oven for 35 to 38 minutes, or until golden and they spring back when very lightly touched in the centre.
- Let cakes cool for 20 minutes in pans. Run a paring knife around the outside of each cake to loosen it from the pan. Remove cakes and let cool to room temperature. Tip: Cakes can be made up to 24 hours in advance. Keep covered in plastic wrap until ready to finish.
- To make jam, peel oranges and remove any white pithy parts on the outside flesh. Separate each orange into segments, and then cut each segment, widthwise, into 1/2” slices. Place orange slices, apricot jam and orange juice in a small pot. Bring to a boil over medium heat, and reduce to a simmer until reduced 1 3/4 cups (around 30 minutes). Cool jam to room temperature, and then refrigerate until needed. Jam can be prepared up to 2 days in advance.
- To make the frosting, place dipping wafers and cream in a heatproof bowl and set over a pot of simmering water. Mix until they are melted and blended with the cream. Remove bowl from heat and let cool for 5 minutes.
- Beat the butter, icing sugar and vanilla for the frosting until well blended. Slowly mix in the melted white chocolate mixture. Now beat the frosting for 3 to 4 minutes until lightened. Scrape the sides of the bowl and beat a few seconds more.
- To finish the cake, place one of the cake rounds on a work surface, hold it in place with the palm of one hand and use your other hand to hold a sharp serrated knife. Use the knife to cut the cake horizontally in half. Now cut the second cake in half.
- Place 2 Tbsp. of the frosting in the centre of your cake plate, and then set on one of the cake halves, cut side up. Spread the top of that cake with 1/4 of the frosting. Now spread that icing with a 1/3 of the mandarin apricot jam.
- Set on another cake half, this time setting it cut side down. Spread the top of that cake layer with 1/3 of the remaining icing. Now spread with 1/2 of the remaining jam. Set on another cake half, setting it cut side up, and top and spread it with 1/2 the remaining icing, and the remaining jam.
- Set on the last half cake, cut side down. Spread the rest of icing on the top of the cake. Decorate the top of the cake with mandarin orange segments and pistachios. When ready to serve, garnish the cake with fresh mint sprigs, if using, and start slicing.
White chocolate dipping wafers are sold in our Bulk Foods Department.