Combine 40g butter, 100ml heavy cream and 50g brown sugar in a pan, dissolve the sugar completely and bring to a brisk boil for 1 min. Take off heat and set aside to cool.

Line a 6-inch springform tin with parchment. Add in 70g crushed macadamia and half of the cooled toffee sauce. Mix well and compact the nuts tightly into an even layer. Freeze for 4 hours or overnight to set.

Dissolve 2g strong instant coffee powder in 120ml hot water. Soak the lady finger biscuits in the coffee and line a 6-inch springform tin. Break the lady finger biscuit if needed to line the tin well. Compact the sponge layer with a spoon and freeze for 2 hours or overnight to set.

Line the base of a 6-inch pan with removable bottom with cling wrap. Add in 60g roughly crushed Oreo biscuits (without cream). Add in 60g melted dark chocolate and mix well. Wear a glove and compact the biscuit base well. Freeze for 2 hours or overnight to set.

Whisk 400ml heavy cream on medium speed until firm peaks. Add in the cooled coffee cream, the remaining toffee sauce and 1.5g sea salt. Whisk just to incorporate *do not over-mix*. Switch to a spatula and mix by hand. Transfer mousse into piping bags and store chilled until assembly.

First, un-mould the frozen nut, sponge and oreo biscuit layers. Work briskly to fill the silicon mould as the layers are easiest to assemble when they are frozen hard.

Place the bottom half of the silicon mould on a plate (for easy handling) and fill the base with a first layer of coffee mousse. Use a pastry brush to even out the mousse and fill the base well. Place in the coffee sponge layer and repeat with the 2nd layer of coffee mousse. Next place in the toffee nut layer.

At this point, fit on the upper half of the silicon mould and repeat with the 3rd layer of coffee mousse. Make sure to fill in the crevices well so that the coffee mousse cake is well formed. If there are visible air bubbles in the mousse, lift the plate and gently tap the mould a few times on the work table to release the air bubbles.

Once the silicon mould is completely filled, level the top with an off set spatula. Lastly, place on the Oreo cookie base, *smooth side up*. Gently press in the cookie base into the mousse so that the base layer is gently compacted with the mousse. Cover the top with parchment and freeze the mousse cake overnight.

Add 3 tsp of gelatin powder to 3 tbsp of cold water. Mix well and set aside to bloom.

Combine 100ml water, 170ml heavy cream, 180g sugar, 20g Dutch cocoa powder, 50g dark cocoa powder and *optional* 2g instant coffee in a heavy bottom pan and whisk until well mixed.

Put the glaze mixture on medium heat and bring to a brisk boil for 2 min. Take off heat and and add in the bloomed gelatin. Sieve to remove any lumps. Set the glaze aside to cool until about 38C - 40C

Once the glaze is almost cooled to 38C un-mould the frozen mousse cake (note: the mousse cake must be glazed frozen) Transfer the frozen cake to a baking rack placed over a lined tray. Glaze the cake evenly from the middle. Rotate the rack if necessary and glaze the sides well.

Have a wooden skewer on hand to prick any visible air bubbles and gently glaze over. Work briskly as the glaze will start to thicken and set. Once the cake is glazed, let it drip for a minute. Then using two off-set spatulas to hold the base, carefully transfer the cake onto a plate.

I decorated with a sprinkle of silver and rose gold dust and a final touch of gold leaf for a cosmic effect. Chill the mousse cake in the fridge and let it thaw until ready to serve. Enjoy.