Nanaimo Slice
Nanaimo Slice, also known as Nanaimo Bars, is a classic Canadian no-bake tray bake made with a chocolatey biscuit base, a creamy custard-buttercream filling and a rich chocolate topping.
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Servings: 12 slices
INGREDIENTS
For the Base
- 115 g Block Margarine or Butter
- 55 g Soft Light Brown Sugar (Light Brown Sugar)
- 55 g Cocoa Powder
- 115 g Digestives Biscuits (Graham Crackers)
- 115 g Desiccated Coconut (Shredded Coconut)
- 115 g Walnuts (chopped)
- 1 Free-range Egg (beaten)
For the Filling
- 100 g Block Margarine or Butter
- 4 tbsp Double Cream (Heavy Cream)
- 3 tbsp Custard Powder (see below for substitutions)
- 250 g Icing Sugar (Powdered Sugar)
For the Topping
- 200 g Dark Chocolate
- 2 tbsp Block Margarine or Butter
EQUIPMENT
INSTRUCTIONS
For the Base
- Line a 20x20cm (8-inch) tin with greaseproof paper and set aside.
- In a medium-large pan, melt the margarine/butter, soft light brown sugar, and cocoa powder over a low heat. Meanwhile, crush the digestive biscuits, either by pulsing in a blender or placing them in a freezer bag and hitting with a rolling pin.
- Once the margarine/butter, sugar & cocoa powder have melted, add the crushed digestives, desiccated coconut & walnuts, and mix until combined. Add the beaten egg and mix through.
- Transfer the base mixture to your pre-lined tin, and press evenly & into the corners of the tray with the back of a spoon. Leave to cool before transferring to the fridge to set, ideally for a couple of hours.
For the Filling
- In a large bowl, sift the icing sugar and custard powder, before adding the margarine/butter and double cream. Beat together until light and fluffy.
- Remove the base from the fridge and spread the custard icing evenly across the top, right into the corners. Return to the fridge whilst you prepare the topping.
For the Topping
- Melt the dark chocolate over a bain-marie or in short bursts in the microwave. Add the margarine/butter and stir until melted through.
- Pour the chocolate mixture over the filling, spread it evenly & right into the corners. Place back into the fridge to set, ideally for a couple of hours.
- When ready to serve, cut the Nanaimo Slice into bars, ideally whilst still in the tray. If it isn't possible to cut in the tin, at least score the chocolate in the tin to avoid the filling pressing out whilst cutting.
IMPORTANT NOTE:
All my recipes are developed using a digital scale and the metric system (grams and millilitres). Cup measurements are available as a conversion but these, unfortunately, won't always be as accurate. For best results, I always recommend baking with a digital scale.
NOTES
Egg Size:
When it comes to eggs, I always buy the Mixed-weight Free-range Eggs. Generally speaking, egg size doesn’t make a huge difference in most baking, unless you are using sizes that lean into the extremes. But with that in mind, medium-sized eggs are probably the best option if you are unsure what size eggs to use.Storage:
Store Nanaimo Slice in an airtight container in the fridge for up to 5 days. The custard filling and chocolate topping keep best when chilled.Freezing:
Nanaimo Slice freezes well. Cut into portions, place in an airtight container and freeze for up to 3 months. Defrost in the fridge overnight before serving.- Digestive Biscuits: Traditionally, Nanaimo Bars are usually made with graham crackers, but digestive biscuits are a readily available alternative in the UK and work perfectly in this recipe.
- Nuts: Walnuts are traditional in Nanaimo Slice, but pecans can be used instead. Or, if you prefer, you can omit the nuts altogether, although the texture of the base will be slightly different.
- Egg in the Base: This recipe uses an egg in the base, as is traditional for many Nanaimo Bar recipes. The egg helps bind the ingredients together, giving a firmer, less crumbly slice. As Nanaimo Slice is a no-bake tray bake, those who need to avoid undercooked eggs may prefer to leave it out, although the base may be slightly more fragile
- Chocolate: Dark chocolate helps balance the sweetness of the custard filling, but milk chocolate can be used if you prefer a sweeter Nanaimo Slice.
- Custard Powder: Birds Custard Powder is a staple in UK homes, but it isn't available everywhere. A good substitution is actually some Vanilla Jello Powder! Alternatively, you can use corn flour (corn starch) and add a little vanilla extract for a custard-like flavour. And for the full custard-powder-effect, you could even add a smidgen of yellow food colouring - although that's purely optional!
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