20-Minute No-Bake Coffee Slice
A layered no-bake dessert combining a buttery Graham cracker and coconut foundation with a rich coffee-infused buttercream topping. This slice requires no oven, making it ideal for warm weather baking or last-minute entertaining. The contrast between the dense, slightly chewy base and the smooth, whipped coffee frosting creates appealing texture, while instant coffee provides deep, bitter-sweet flavor that balances the sweetness of condensed milk and confectioners sugar. The coconut adds tropical warmth and moisture. Best suited for home bakers seeking no-oven desserts, this version stands apart by using both condensed milk and fresh butter in the base for richness, and by whipping the coffee topping to silky lightness rather than leaving it dense. Serve chilled as petit fours at afternoon gatherings or as casual squares with tea.
Ingredients
- 9 oz graham crackers, crushed
- 1 cup unsweetened shredded coconutshredded coconut (sweetened)1:1flavor
adds residual sugar to base, reduce confectioners sugar in topping by 2 tablespoons
- 1 ¾ cups sweetened condensed milk
- 22 tbsp butter, divided, 60 melted for base and 250 for toppingcoconut oil1:1texturedairy-free
creates slightly denser base and topping, adds subtle coconut flavor
Full guide → - 3 cup powdered confectioners sugar, siftederythritol powdered sweetener1:1nutrition
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- ¼ cup milk
- 2 tablespoon instant coffeecold brewed coffee2 tablespoonFull guide →
Instructions
- 1
Combine sweetened condensed milk and melted butter in a small jug, stirring until blended.
- 2
Crush graham crackers in a food processor, transfer to a large bowl, and mix with unsweetened shredded coconut.
- 3
Pour condensed milk mixture into dry ingredients and stir until fully combined.
- 4
Grease and line a brownie tray with non-stick baking paper, press mixture firmly into base, and refrigerate.
- 5
Heat milk in microwave until hot, stir in instant coffee until dissolved, and let cool slightly.
- 6
In a large bowl, cream butter with sifted powdered confectioners sugar using a hand mixer for 5 minutes.
- 7
Beat cold coffee mixture into the creamed butter and sugar until smooth and fluffy.
- 8
Spread topping over chilled base, smooth to cover completely, and refrigerate for 20 minutes or until set.
- 9
Cut into cubes and serve chilled.
Tips
Crush crackers to varied textures rather than fine crumbs: some larger pieces create pleasant grittiness in the base. Pulse the food processor rather than running continuously.
Ensure coffee mixture cools before beating into buttercream or the butter will melt and texture collapses. Prepare coffee while the base chills.
Press base firmly and chill thoroughly before topping to prevent layers from shifting. Use an offset spatula dipped in warm water for smooth topping application.
Good to Know
Keep refrigerated in an airtight container for up to 5 days. The base maintains texture and the topping remains stable when cold.
Prepare up to 2 days in advance. Assemble completely, cover, and refrigerate. Do not freeze; condensed milk base and whipped topping do not freeze well.
Serve chilled, cut into small cubes. Pairs well with hot coffee, tea, or as part of a dessert platter.
Common Mistakes
Whip the coffee topping thoroughly to achieve lightness; neglecting to cream butter and sugar for the full 5 minutes results in a dense, greasy topping.
Skip pressing the base firmly into the pan to avoid a crumbly, loose texture that separates from the topping layer.
Add warm coffee to room-temperature buttercream to avoid melting the butter and breaking the emulsion.
Substitutions
Dairy-Free Swaps
creates slightly denser base and topping, adds subtle coconut flavor
Full guide →General Alternatives
adds residual sugar to base, reduce confectioners sugar in topping by 2 tablespoons
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FAQ
Can I use sweetened coconut instead of unsweetened?
Yes, but reduce the powdered confectioners sugar in the topping by 2-3 tablespoons to avoid excessive sweetness. The base will taste notably sweeter overall.
What if I don't have instant coffee?
Use 1/4 cup strong brewed coffee cooled to room temperature, omitting the additional milk. The coffee flavor will be slightly less intense but still present.
Can I freeze the coffee slice?
No. The condensed milk base and whipped topping do not freeze well and become unpleasantly grainy when thawed. Refrigerate for up to 5 days instead.