Lemon & Blueberry White Chocolate Ganache Slice
A luscious slice combining tangy lemon, sweet blueberries, and creamy white chocolate ganache. Perfectly set on a buttery shortbread base, this dessert is easy to make, fridge-friendly, and guaranteed to impress.
Ingredients
Shortbread Base
- 1⅔ cup plain all purpose flour 200g
- ½ cup icing sugar 65g
- 175 grams melted butter
- 1 tsp vanilla essence
White Chocolate Lemon Ganache Filling
- 200 grams white chocolate (buttons, drops or chopped)
- ½ cup cream 125ml
- zest of 2 lemons
- 1-2 tbsp lemon juice depending on level of lemon flavour you want
Blueberry Swirl
- 1½ cups frozen blueberries (or fresh)
- 3 tbsp white sugar
- 1 tbsp lemon juice
- 1 tsp cornflour
Instructions
Shortbread Base
- Preheat oven to 170°C and line a 20cm square slice tin.
- Mix flour, icing sugar, melted butter, and vanilla until a soft dough forms.
- Press evenly into the lined tin.
- Bake for 18–20 minutes until lightly golden.
- Cool completely.
Blueberry Swirl
- In a saucepan, combine blueberries, sugar, and lemon juice over medium heat.
- Cook until berries release juices and start thickening.
- Stir in cornflour mixture and cook 1–2 minutes until glossy and thick.
- Cool fully before using.
White Chocolate Lemon Ganache
- Heat cream until just steaming (not boiling).
- Pour over white chocolate and let sit 1 minute.
- Stir until smooth.
- Add lemon zest and lemon juice, stirring gently to combine.
Construct the Slice
- Pour ganache over the cooled base.
- Spoon cooled blueberry compote on top.
- Swirl with a knife for that marbled finish.
- Chill for at least 6 hours, preferably overnight. Do not rush the chilling. This is where it sets properly.
Notes
If the ganache doesn’t set properly
If your slice is still soft after chilling...It may not have chilled long enough this slice really needs at least 6 hours, ideally overnight. The cream may have been too hot, which can slightly affect texture. The white chocolate ratio matters!! Make sure you used the full 200g. If it’s very soft, pop it back in the fridge longer. It will continue to firm up.If the ganache splits or looks grainy
This can happen if...The cream was too hot, The mixture was stirred too aggressively, Lemon juice was added too quickly To fix it:Gently warm the mixture and stir slowly until smooth again. Always add lemon juice after the chocolate has fully melted and combined.
If the blueberry swirl sinks
The compote needs to be fully cooled and thickened before swirling. If it’s still warm or too runny, it can bleed into the ganache instead of sitting on top.If your base is too crumbly
- Make sure the butter amount was correct.
- Press the base firmly into the tin before baking.
- Let it cool fully before adding filling...warm base = soft bottom.