AT A GLANCE
There's a lot going on in this cake - layers of brown sugar cake, salted caramel, cream cheese frosting and brown sugar crumb for texture. It all adds up to salty-sweet deliciousness, which is well worth every step. To make things easier, the caramel, crumb and frosting can all be made several days ahead.
|01||For salted caramel, stir sugar and 100ml water in a saucepan over medium-high heat until sugar dissolves, then brush down sides of pan with a wet pastry brush to remove sugar crystals and boil until dark caramel (7-8 minutes). Remove from heat, carefully add cream (hot caramel will spit), then add butter and 2 tsp sea salt flakes and swirl to combine. Cool, then refrigerate in an airtight container until required. Caramel will keep for up to 5 days.|
|02||For brown sugar crumb, preheat oven to 170C and line an oven tray with baking paper. In a bowl, rub butter into dry ingredients and ½ tsp sea salt with your fingertips to form coarse crumbs, spread on prepared tray and bake until golden brown (6-8 minutes). Cool completely, then store in an airtight container until required.Brown sugar crumb will keep for up to 5 days.|
|03||Keep oven at 170C and butter and line three 18cm-diameter cake tins with baking paper (see note). Beat sugars and butter in an electric mixer until pale and fluffy (6-7 minutes), scrape down sides of bowl, then beat in eggs one at a time, beating well and scraping down sides of bowl between additions. Add flour and buttermilk alternately in 2 or 3 batches, beating to just combine, then mix in vanilla. Combine vinegar and bicarbonate of soda in a bowl, stir into batter, then divide among cake tins and bake, swapping and turning tins partway through cooking, until golden brown and a skewer inserted withdraws clean (25-30 minutes). Cool in tins for 10 minutes, then turn out onto wire racks to cool completely. Trim tops flush with a serrated knife.|
|04||For cream cheese frosting, beat butter and sugar in an electric mixer until pale (4-5 minutes), scrape down sides of bowl, then add cream cheese and beat until fluffy (6-8 minutes).|
|05||To assemble, place a cake on a tray, spread with cream cheese frosting to 5mm thick, drizzle with a little salted caramel and scatter with a layer of brown sugar crumb. Repeat layering, finishing with last cake, then spread remaining cream cheese frosting over top and sides of cake with a hot palette knife. Refrigerate until required.|
|06||Serve cake with warmed salted caramel and extra brown sugar crumb for scattering.|