Since the kids were babies, our family birthday cake of choice has been Devil’s Food cake with French Vanilla Icing and Smarties. Yes, cake mix from a box, with icing in a plastic container, pre-made. Every year I would send enough cupcakes for the entire class for the birthday, and we also had a full-sized cake at home. Any suggestion of a variation was greeted with a sour look and a fast shake of the head. Until last year, that is, when daughter Lauren produced Better-Than-Crack-Brownie Cakes for Kirsten & Mike’s respective birthdays at the end of March. When your daughter is a French-trained professional chef, it does put your previous efforts into rather a harsh perspective!  

The cakes were sublime. A rich brownie base topped with a thin coating of peanut butter crackle, upon which rested a thick layer of peanut butter mousse and the topped off with what I thought was chocolate ganache, but turned out to be Chocolate Mirror.

That was that. Allegiances shifted immediately. This was now the New Favourite. I had to exercise iron self-control to not inhale an entire cake in one sitting, but after parcelling out pieces to departing family members, I managed to eke out my consumption over the next few days. I shuddered to think of the caloric value and contented myself with the notion that it was an infrequent indulgence.

Lauren produced a deconstructed version in small mason jars for a family dinner in October, so I decided to try my hand at these for our Gibson Girl Plate dinner party. I used antique champagne cups for the dinner party but did have some leftovers to make up some mason jars portions which were distributed among the family.

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Better-Than-Crack Brownie Cake

A sublimely rich chocolate brownie base topped with peanut butter mousse and a layer of chocolate.

  • Total Time: 120



For the brownie base

  • 300 g eggs (4 large)
  • 200 g white sugar
  • 180 g brown sugar, packed
  • 227 g melted butter
  • 150 g cocoa
  • 10 ml vanilla extract
  • 60 g flour
  • 3 g salt

For the peanut butter mousse

  • 250 g cream cheese, cut into 1” cubes
  • 270 g peanut butter
  • 150 g icing sugar
  • 250 g cream (35%)

For the chocolate mirror

  • 10 g gelatin sheet
  • 210 g white sugar
  • 110 g water
  • 65 g cocoa powder
  • 65 g cream (35%)
  • 50 g dark chocolate (70-80%), chopped into pieces

For garnish (optional)

  • Chopped Reese’s Pieces, Reese’s Peanut Butter Cups, Chocolate Covered Peanuts or Yoghurt Covered Peanuts


Make the brownies

  1. Preheat the oven to 300°F Convection Bake (or 325°F non-convection)
  2. Line an 8″ square pan with parchment paper by crossing two sheets folded to fit snugly in width, with sufficient length to lift the brownie from the pan when baked.
  3. Beat the eggs in a mixer fitted with the whisk attachment until fluffy and pale yellow. Add both sugars and beat until fluffy. Add the remaining ingredients and mix until combined. The batter will be quite thick
  4. Spread the batter carefully into the parchment-lined pan. Bake for 45 minutes, or until a toothpick inserted in the centre comes out clean. Let cool slightly and then lift the brownie onto a rack to cool completely.

Make the peanut butter mousse

  1. Whip the cream until it forms stiff peaks in a mixer fitted with the whisk attachment. Remove the whipped cream to another bowl. Using the paddle attachment, mix the cream cheese and icing sugar in the mixer bowl until thoroughly combined. Add the peanut butter and beat until combined. Fold in the whipping cream by hand. Set aside in the fridge until ready to assemble the brownies or parfaits.

For the chocolate mirror

  1. Bloom the gelatin sheets in a medium bowl with lots of cold water for at least 10 minutes.
  2. Stirring constantly with a whisk, bring the sugar, water, cocoa powder and cream to a boil in a medium saucepan.
  3. Add the chocolate pieces and stir until combined.
  4. Squeeze the excess water off the bloomed gelatine and add it to the pot. Stir until dissolved.
  5. Place a fine-mesh sieve over a jar or large measuring cup and pass the mixture through the sieve. Cover the jar with plastic wrap and chill in the refrigerator for at least 4 hours.
  6. Warm the mixture to pouring consistency before using it. You can heat it gently in the microwave on defrost to get it going, and then mix gently.

Assembling the cake

  1. Spread the peanut butter mousse over the brownie base and chill until firm.
  2. Gently heat the Chocolate Mirror and pour over the peanut butter layer.
  3. Sprinkle your choice of chopped garnish over the top.
  4. Chill until ready to serve.


  • In the original cake, Lauren put yet another layer between the brownie and the peanut butter mousse, which I believe consists of peanut butter, sugar and Rice Crispies. When I nail her down on this layer, I will update the recipe. As I was making parfaits, I didn’t have enough room for this extra layer, and didn’t think to get the specifications for it at the time.
  • If making parfaits, use an appropriately sized biscuit cutter to cut the brownie for the bottom of the cup. Then add a layer of mousse about 1″ thick and chill until firm. Pour the chocolate mirror over the top and garnish it with your choice of decoration.
  • If you are making these in small mason jars, you can either use scraps of brownies from a more elegant presentation (like the parfaits), or even bake the brownies right in the jars.
  • Author: Lauren Kain
  • Prep Time: 60
  • Cook Time: 60


  • Serving Size: 12