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🍓🌸 Raspberry Rhubarb Cake – A Colorful Mousse Delight with Spider Glaze

A stunning layered dessert with rhubarb blondie, praline crunch, berry gel, and a tangy mousse – all wrapped in vibrant triple-color glaze.
This raspberry rhubarb cake combines tangy fruit mousse, blondie base, praline crunch, and an artistic spider glaze – a perfect showstopper.
This Raspberry Rhubarb Cake is a true eye-catcher – not just for its flavor but also its mesmerizing look. Layer by layer, it tells a story of textures and contrasts: a moist rhubarb blondie, crunchy white chocolate praline, fruity raspberry-rhubarb gel, and a smooth mousse. It’s all crowned with a triple-colored glaze (purple, pink, and red) and topped with a delicate white spider glaze that creates a gorgeous marble effect.
While the blondie is delicious on its own, the combined layers elevate this dessert to a bakery-style masterpiece. If you enjoy desserts that are both stunning and bursting with bright fruity flavors – this one’s for you.
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Prep Time 1 hour 30 minutes
Cook Time 30 minutes

Ingredients
  

✳️ Rhubarb Blondie Base

  • 150 g butter
  • 150 g sugar
  • 2 eggs
  • 2 tsp vanilla sugar
  • 100 g white chocolate chopped
  • 75 g rhubarb diced
  • 50 g coarsely grated marzipan
  • 50 g all-purpose flour
  • 1 pinch of salt

✳️ White Chocolate Praline Crunch

  • 30 g sugar
  • 30 g water
  • 65 g almonds
  • 30 g white chocolate

✳️ Raspberry-Rhubarb Gelée

  • 1 sheet gelatin
  • 50 ml raspberry-rhubarb juice or shot e.g., from Pure Shots

✳️ Raspberry-Rhubarb Mousse

  • 3 sheets gelatin
  • 125 g raspberries
  • 125 g rhubarb chopped
  • 50 g sugar
  • Seeds from ½ vanilla bean or 1 tsp vanilla sugar
  • Juice of 1 lemon
  • 200 ml heavy cream
  • 100 g Greek yogurt 10%

✳️ Glaze + Spider Glaze

Main Glaze:

  • 5 sheets gelatin
  • 100 g acacia honey
  • 150 g sugar
  • 100 g water
  • 100 g sweetened condensed milk
  • 110 g white chocolate chopped
  • Gel food coloring: pink red, and purple

Spider Glaze:

  • 50 g mirror glaze miroir gel
  • White gel food coloring

Instructions
 

🍰 Preparation

  • Rhubarb Blondie Base
  • Preheat oven to 175°C.
  • Melt the butter and set aside.
  • Whisk eggs, sugar, and vanilla until light and fluffy. Stir in melted butter.
  • Fold in chopped chocolate, rhubarb, and marzipan.
  • Add flour and salt and mix.
  • Pour into a 20–22 cm springform pan lined with parchment and bake for 20–25 minutes.
  • Cool completely, then cut out a 14 cm disc using a ring. Wrap the inside with acetate and chill.

White Chocolate Praline Crunch

  • Roast almonds at 200°C for 5–6 minutes.
  • In a saucepan, boil sugar and water until golden caramel.
  • Add roasted almonds while stirring on heat.
  • Pour mixture onto parchment paper to cool completely.
  • Blend until the natural oils release and the praline is smooth.
  • Melt white chocolate, stir into praline, and pour over blondie base. Chill to set.

Raspberry-Rhubarb Gelée

  • Soak gelatin in cold water.
  • Warm the juice to around 40–50°C, then melt in gelatin.
  • Let it cool slightly, then pour over praline layer. Freeze until fully set.

Raspberry-Rhubarb Mousse

  • Soak gelatin in cold water.
  • Simmer raspberries, rhubarb, sugar, lemon juice, and vanilla for 10 minutes.
  • Blend and strain. Stir in gelatin and cool.
  • Whip cream to soft peaks and fold in Greek yogurt.
  • Add the cooled fruit purée.
  • Pour into an 18 cm silicone mold, then gently press the frozen cake insert (gelée side down) into the mousse.
  • Freeze overnight until fully set.

Main Glaze (Triple Color)

  • Soak gelatin in cold water.
  • Bring honey, sugar, and water to a boil. Remove from heat, stir in condensed milk and gelatin.
  • Pour over white chocolate and blend carefully with an immersion blender.
  • Cool to 36°C, then divide into three bowls. Color each with pink, red, and purple.
  • Pour small amounts from each color alternately into a clean jug to create a swirl.

Spider Glaze

  • Melt miroir gel and mix with white food coloring. Bring to same or slightly higher temp as main glaze (36–38°C).

🧩 Assembly & Glazing

  • Place frozen cake on a rack over a tray.
  • Pour the colored glaze over the entire cake evenly.
  • Dip a large palette knife into the white spider glaze and gently swipe across the surface for a marbled spider effect.
  • Transfer cake to serving board and let thaw in fridge for 1–2 hours before serving.