Chocolate and passion fruit mirror glaze cake
Moist dark cocoa sponge, zingy passion fruit curd insert and velvety caramelized white chocolate mousse under a dark chocolate shiny glaze. An elegant cake, both in taste and looks.
Equipment
- whisk
- 19cm Ø springform
- 22cm Ø springform
- heat resisting bowl
- 24cm Ø silicone mould
- stand or hand mixer with whisk attachment
- plastic film
- cake leveler/ cutting wire (optional)
- kitchen/ chocolate thermometer
- immersion blender and a tall cup
- a sieve
Ingredients
For the dark cocoa cake base:
- 100 g all-purpose flour
- 30 g pure cocoa powder
- 1/2 tsp baking powder
- 1/2 tsp baking soda
- 1 egg
- 1 pinch salt
- 100 g caster sugar
- 30 g vegetable oil
- 100 ml kefir (or yogurt)
- 100 ml boiling water
For the passion fruit and lime curd:
- 5-6 passion fruits
- 1-2 limes
- 6 egg yolks
- 1 whole egg
- 100 g caster sugar
- 30 g unsalted butter
For the mousse:
- 2 tsp gelatin powder
- 3 tbsp cold water
- 200 g caramelized white chocolate (or white chocolate) (I use Callebaut Gold callets)
- 140 g whipping cream
- 500 g whipping cream chilled
For the mirror glaze:
- 2 tsp gelatin powder heaped
- 50 ml cold water
- 100 g sweetened condensed milk
- 150 g caster sugar
- 25 g pure cocoa powder
- 100 ml water
- 175 g dark chocolate around 50% (I use Callebaut callets 54,5%)
Extra, for decoration:
- crunchy dulcey pearls
Instructions
Phase 1 - prep the element
- Bake the cake and prepare the passion fruit & lime curd 1-2 days ahead. Preheat oven to 170C (no fan). In a small bowl add the flour, cocoa, baking powder and baking soda, stir with a fork and set aside. Place some water to boil into a kettle. Meanwhile, place the egg, a pinch of salt and the sugar in a medium bowl and mix by hand with a whisk for a minute or two, until pale yellow. Add the oil and whisk again until you get a creamy consistency. Then add the kefir/yogurt and whisk again just until combined. Pour the boiling water while stirring with the whisk. Then run the flour and cocoa mixture through a sieve directly into the mixing bowl. Whisk until combined. You will get a runny batter, that is how it's supposed to be.
- Pour the batter into the Ø22cm spring form, lined with baking paper only on the bottom. Bake for 25-30 minutes, or until a toothpick comes out clean. Let cool in the form until you'll be using it.
- Prepare one batch passion fruit & lime curd, following the instructions here. Let it cool down, then pour in the Ø19cm spring form lined with cling film and place in the freezer for at least 4h before using it.
Phase 2 - building the cake
- In a tiny bowl add the gelatin powder and the cold water and let it sit for 5-10 minutes. In the meantime, add the chocolate and the small portion of whipping cream in a heat resistant bowl and melt it over a bain marie. When the chocolate has melted, set aside.
- Then melt also the bloomed gelatin and add to the melted chocolate mix. Stir until well incorporated then let sit for 10-15min., stirring from time to time.
- Pour the cold whipping cream in a mixing bowl. Start whisking on medium-high speed until soft peaks start forming. Check the consistency from time to time. You want to get a light and soft creamy one. Not too stiff, as the gelatin will do its job and make it set. Add 2 tbsp. of the whipped cream to the melted chocolate which should not be that warm any longer. Keep en eye on it, as you don't want it to get too cold and stiff either. Stir in with a spatula just until incorporated, then add to the whipped cream and fold gently.
- Place the silicone form on a cutting board (you want it to be steady when moving around). Pour about half to 2/3 of the mousse in the form, then place the it in the freezer, ideally in the fast freeze container, to set for about 20 minutes. That will help firm up a bit and hold the passion fruit curd insert without sinking.
- In the meantime use a cake cutting wire or a sharp long knife to level the dark cocoa cake sponge you baked previously.
- Remove the silicone mould from the freezer, pour the extra mousse in there (it will have set a bit meanwhile, so you might need a small spatula to distribute it evenly. Remove the passion fruit curd insert from the freezer and take it out of the plastic film. Place in the middle of the mousse and gently press it until the mousse raises to the same level with the curd ring. Then add the dark cocoa sponge on top of the curd, in the center. Gently press down until it levels up to the edges of the silicone form. There will be a little mousse excess, just remove it with a spatula. When everything is nicely even, place the silicone mold in the freezer overnight. Don't forget to use the cutting board underneath to keep it steady.
Phase 3 - decoration
- In a small bowl add the gelatin powder and the small portion cold water and let swell. Add the chocolate (chopped into small pieces if it comes in tablet or large chunks) into the tall blender cup and set aside.
- In a small saucepan add the condensed milk, sugar, water and cocoa powder. Place on a medium heat and stir with a whisk until everything is combined. Bring it just to a boil and remove from heat. Add the bloomed gelatin and stir until dissolved. Pour the hot mixture over the chocolate, and let sit for about 5 minutes, until the chocolate pieces have melted.
- Submerge the blender into the hot chocolate mixture and blend until smooth. Try to not keep the blender perpendicular on the surface, but on an angle. That will help you avoid getting air bubbles into the glaze. When you're done blending, run the mixture through a fine sieve to get rid of small air bubbles and make sure it is all smooth. Place the thermometer into the glaze. You will need to pour the glaze over your frozen cake when it reaches a temperature between 37 and 35 C.
- When the temperature is almost there, take the cake out of the freezer and remove it from the silicone form. Place it on an upside-down cup or glass, above a tray where the excess glaze can drip. Pour the glaze once it goes under 37C (not lower than 35C), starting from closer to the edges and finishing in the center of the cake. That way you make sure the edges are well covered. When the glaze stops dripping, run a little pastry spatula or knife under the bottom edge, to remove the excess glaze hanging. with two long cake spatulas or two long knives lift the cake and place on a serving plate or on a round cake cardboard.
- Decorate simply with a necklace of crunchy dulcey pearls around the bottom of your mirror glaze cake, to cover the imperfections. Place in the fridge for about 4 hours before serving, so it will easily de-freeze. Admire the layers when cutting into it and enjoy!