This deliciously unusual brioche cake is soaked with mojito mint-infused maple syrup, fresh lime juice and rum like a rum baba or savarin but layered with dulce de leche buttercream – easy and yummy with the caramelised condensed milk flavour reminiscent of brown sugar mojitos. When I looked online this kind of cake didn’t seem to exist but never mind, the important thing is it’s light, delicious, not too sweet and tastes like a mojito!  Yay!  And to make it mocktail leave out the rum.  Accompany with delicious mint-infused cream and natural greek yoghurt, or just serve with a dollop of yoghurt.  I made a sourdough brioche but a standard yeasted brioche is fine – both recipes are given.   I even did a loaf-shaped nobake version with a shop-bought French unsliced brioche – also delicious!  You can make smaller cakes with brioche buns or even adapt and make with a sponge!  Decorate with stars piped with dulce de leche buttercream or cream, sprigs of fresh mint, slices of lime, white chocolate shapes, macarons or meringue kisses.  Sprinkle a little icing sugar on top.  Tada!  A Mojito Oblivion brioche layer cake!  It’s been named because it’s a special creation made for my lockdown birthday and surprisingly scrumptious!  It may not be well-known or trending but it sure is delicious…!  Maybe you could make one too and help start a trend…  😉

RECIPE

The inspiration for this cake came from having a bundt-shaped sourdough brioche in the freezer, ingredients for a mojito and an opened jar of dulce de leche in the fridge.  And I felt a bit lazy so didn’t want to bake anything.  After days wondering what to make for my birthday cake I realised these ingredients could all come together! 🙂

If you’d like a more traditional mojito savarin, like a rum baba, please go to my Babajitos mojito rum babas recipe here. Savarins or babas are more spongy, moist and cake-like.  This brioche cake is more bready and fluffy but also moist and tasty, plus it works with buttercream layers.

Brioche

You can buy an unsliced loaf of brioche and work with that.  For my latest prototype it was a long-life French one in a plastic bag, not top-quality but easily transformed into a delicious no-bake loaf-shaped layer cake.  I used 315g/11oz of the loaf. The whipped cream goes between the layers.  Yum yum.

To make your own brioche the sourdough brioche recipe is here (in my basics section).  With the quantity in the recipe you can make one low bundt-shaped brioche and two loaves, as in the photo.  Don’t fill your bundt tin too much.

Sourdough levain

• 20g/scant 1/8 cup sourdough starter
• 100g/ml tepid water (between 23-27ºC/74-80ºF)
• 100g/3/4 cup less 1 tsp organic strong white bread flour

Dough

• 600g/4 and 3/4 cups strong white flour (or half strong white flour and half plain or 00 flour – all 00 flour also works well)
• 120g/ml full-fat milk
• 180g/scant 1 cup of your prepared active sourdough levain (made 6 – 10 hours ago so it’s bubbly and more or less doubled in size) – it will be almost all of your prepared levain less 1 tablespoon.
• 300g beaten egg at room temperature (about 5 and 1/2 medium-large free-range eggs)
• 240g/1 cup unsalted butter cut into smallish pieces and softened at room temperature (good quality French-style like le Président)
• 60g/1/4 cup unrefined sugar – I use unrefined golden caster sugar
• 12g/2 tsp fine sea salt

Otherwise there’s a standard brioche recipe here (optionally lower-gluten) from my blog archives.  Or use your own brioche recipe.

A second batch of prototypes was made with a smaller sourdough bun and mini-bundts.

I prefer the large cakes but maybe the smaller ones just need extra soaking and cream on the side.

Anyway, allow the brioche to cool (or defrost) completely before assembling the cake.  And construct…

Ingredients

Here’s a printable illustration (click on image) with the ingredients and decorative elements you’ll need.

Mint-infused cream and yoghurt (optional) – prepare 3 or 4 hours before or previous night

• 100g/ml liquid whipping cream, 35% fat
• 2g/small handful fresh mint leaves, weigh when dry then rinse, pat dry with paper towel and tear slightly
• to add later: 
• optional 10g (1/2 tbsp) pure maple syrup or sugar
• 25-45g /1 and 1/2 to 2 and 1/2 tbsp natural unsweetened greek yoghurt (to taste, check texture as you go)

Place mint in cream to infuse 3-4 hours or overnight in fridge (test cream occasionally to check flavour).  Keep in fridge until needed.

Soaking syrup

• 150g/ml water, brought to the boil (I used mineral water)
• 30g/ml lime juice, freshly-squeezed (grate lime zest before juicing to sprinkle on cake later)
• 85g/4 tbsp + 1 tsp pure maple syrup
• 4g/good handful fresh mint leaves, weigh when dry then rinse, pat dry with paper towel and tear slightly
• 40g/2 tbsp white rum, to taste (or leave out rum and replace with a little more water, lime juice and maple syrup)

1. Combine just-boiled hot water with lime juice and pure maple syrup in a jar or bowl.  Allow to cool 30 minutes or so.
2. Add fresh mint leaves, cover and infuse 1-2 hours or more.
3. Test syrup – you should taste mint but it shouldn’t be too overpowering or bitter.  When the flavour is to your taste take leaves out (reserve in case).
4. Stir in rum.  Test again to make sure you like the flavour (add more rum, lime or maple syrup if needed and/or put mint leaves back in).

Assembling Part 1 – slicing and soaking

Note 1:  To make re-assembling layers easier use a finger to draw a vertical line down one side of the brioche with flour or icing sugar.  This will disappear once soaked so carefully move layers across each other in the same position without turning.  If you forget just re-position layers as best as possible so they sit nicely.

Note 2:  for the tall loaf-shaped brioche slice into 4 horizontal layers, first cutting in half then cutting each half in half.

1. Slice bundt brioche into 3 or more horizontal layers with a serrated bread knife.  If using small brioches 2 layers might be enough – brioche layers should be about 2.5cm/1in thick or less.
2.  Place bottom layer(s) on serving plate.  Brush with or spoon over cooled soaking syrup evenly over surface.  Allow to soak in then repeat a few times.  Make sure the brioche is well-soaked so it all softens but don’t make it so soft it falls apart.
3. Repeat to soak other layer(s).
4. Check brioche layers are nicely soaked (brush with more syrup if needed) then rest 15-20 minutes.  If you have extra syrup set by to serve with cake or … make a mojito!
5. Meanwhile make buttercream.

NOTE:  it’s important cakes be well-soaked. My smaller sourdough buns were a bit dry because I didn’t have much syrup – should have made some more.  

Dulce de leche buttercream

• 100g/1/2 cup less 3 tsp butter, good-quality French-style like le Président
• 173g/1/2 cup + 1 tbsp dulce de leche
• 1/8 to scant 1/4 tsp fine sea salt, to taste

1. Make sure butter and dulce de leche are both at room temperature (differing temperatures can cause combined mixture to separate).  Whisk together with salt until creamy.
2. Keep whisking until buttercream is light and fluffy.  It might seem it’s not happening but persist and the buttercream will suddenly start holding with peaks forming (after 10 minutes or more by hand and 5 minutes on standmixer/with electric handwhisk).  It should look lighter in colour.  Note: if it separates warm a few minutes on a bain marie and whisk vigorously until creamy again.

For more details on buttercream and homemade dulce de leche please see my dulce de leche chocolate cake post here.

Assembling Part 2 – layering

• A little apricot jam (optional, for extra shine)
• For the loaf cake the cream goes inside (see instructions further down)

1. Brush outer surface of brioche layers with apricot jam (warm jam gently if difficult to spread) to give the brioche a shine.
2. Pipe thinnish layer of buttercream (a little less than half) on the base brioche layer.
3. Carefully place middle layer on top and cover with thinnish layer of remaining buttercream, reserving a little to decorate the top with piped stars.
4. Place final brioche layer on top.
5. Pipe several buttercream stars on top to decorate.
6. Place in fridge 1-2 hours.

Loaf-shaped cake (or brioche with no bundt hole)

• Follow the layering process as for the bundt-shaped brioche above but adding piped cream stars on top of each buttercream layer, using just under 1/3 of the cream for each layer (whisk cream as per instructions in the next section).  Save a little cream to pipe a few stars on top.

Whisking the cream and decorating

1. Remove mint leaves from cream (optionally with sieve) and whisk to soft peak.
2. Add maple syrup and greek yoghurt and whisk to stiff peak (when you turn the bowl upside down the cream doesn’t slip out).
3. Pipe into middle of bundt cake and pipe stars on top, or serve on the side for round or small brioches.
4. Decorate with slices of lime and fresh mint leaves and sieve a little icing sugar over the cake.   If you have them add dulce de leche macarons and mini meringue kisses (stocked in my freezer) and white chocolate shapes.
5.  Sprinkle with finely-grated lime zest.

Eating and storing

Store in fridge a few hours then allow to come to room temperature 20-30 minutes or more before eating. After assembling the loaf cake was immediately moist and could be served almost immediately after a little chilling in the fridge.

The cake keeps in the fridge up to 3 days or more.

Serve with mint-infused cream and yoghurt or just natural greek yoghurt.

It’s easy to have two slices of this Mojito Oblivion brioche layer cake!

It’s light, feathery and moist with a little mojito kick and the lime adding that sweetly citric touch.  Yum yum.

Bye for now dears!  Hope you’re enjoying a little new outdoor freedom, as well as some happy baking and eating! 🙂 Stay safe. Lili x