This easy and delicious No Bake Chocolate Fish Slice has a biscuit base and chocolate icing on top.

This Chocolate Fish Slice is the ultimate cafe-style treat that kids just love. It's the baking WITH the complimentary chocolate fish as the icing on the cake. Crunchy on the bottom and chewy on the top this slice will satisfy your mid morning cravings nicely and perfect for your next kids birthday party! My No-Bake Lemon Slice is another favorite.

A bonus of this no-bake slice means you don't even have to turn the oven on. The base ingredients are simply heated on the stove top before being pressed into the tin and the finished slice sets in the fridge. I have so many more No Bake Slices on my website, i just love them!

Ingredient notes:

- Chocolate Fish: They are a much-loved Kiwi treat that bring a mix of nostalgia and pure comfort. Any brand will do.
- Plain Biscuits: Using plain biscuits in a slice is a simple but essential way to create structure, texture and that classic homemade feel. See the FAQ's for other options you can use.
- Butter: You may have noticed that I pretty much always use salted butter in my baking recipes. I love the salty flavour it adds to sweet slices.
Note: Scroll to the recipe card for the ingredients, quantities and the full method.
Step by step instructions:
Line a slice tin (approx 19 x 29cm) with baking paper. Crush the biscuits until you have a good balance of some fine crumbs and some chunky pieces. This can be done in a food processor in a few pulses (do not blitz completely!) or in a sealed plastic bag with a rolling pin.


Melt the butter, cocoa and brown sugar together in a saucepan, stirring to dissolve the sugar. Remove from the heat, add the vanilla and milk and stir until combined. In a large mixing bowl combine the crushed biscuits with the chocolate mixture.


Press into the lined slice tin. You may have to use your hands for this. Flatten top with the back of a metal spoon. Chill base in the fridge while you make the topping.


Topping: Combine icing sugar and cocoa in a bowl, then stir in melted butter, adding boiling water as needed to loosen mixture, and whisk out any lumps. Spread over the base and place the chocolate fish on top.


Refrigerate for at least 4 hours or overnight before cutting into slices.

Recipe FAQs:
It takes around 3-4 hours in the fridge (even better overnight) but you can speed up the process by putting it into the freezer for 30 minutes.
You can use any plain biscuits like Superwines, Milk Arrowroots or Maries. Even Krispies would work too.
My slice tin is 29 x 19 cm, the brand is Haven and I purchased from Farmers in New Zealand.
Storage:
Store any leftover Chocolate Fish Slice in an airtight container in the fridge for up to a week, (if it lasts that long!).
Keep them ready to-go in the freezer for up to three months.
Top tips:
I've placed the chocolate fish on in a grid and cut the slice pieces around each one. If you wanted to cut smaller slices, you could arrange the chocolate fish randomly over the top then cut through them.
Related Recipes:
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Chocolate Fish Slice
This easy and delicious no-bake chocolate fish slice has a biscuit base and chocolate icing on top.
Ingredients
- 250g butter
- ¼ cup cocoa
- 1 cup brown sugar
- 1 tsp vanilla extract
- ½ cup milk
- 2 packets Marie or Wine biscuits, (250g each)
Topping
- 2 cups icing sugar
- 2 Tbsp cocoa
- 2 Tbsp melted butter
- 1-2 Tbsp boiling water
- 16 mini chocolate fish
Instructions
- Line a slice tin (approx 19 x 29cm) with baking paper.
- Crush the biscuits until you have a good balance of some fine crumbs and some chunky pieces. This can be done in a food processor in a few pulses (do not blitz completely!) or in a sealed plastic bag with a rolling pin.
- Melt the butter, cocoa and brown sugar together in a saucepan, stirring to dissolve the sugar. Remove from the heat, add the vanilla and milk and stir until combined.
- In a large mixing bowl combine the crushed biscuits with the chocolate mixture. Press into the lined slice tin. You may have to use your hands for this. Flatten top with the back of a metal spoon.
- Chill base in the fridge while you make the topping.
- Topping: Combine icing sugar and cocoa in a bowl, then stir in melted butter, adding boiling water as needed to loosen mixture, and whisk out any lumps. Spread over the base and place the chocolate fish on top.
- Refrigerate for at least 4 hours or overnight before cutting into slices.
Notes
My slice tin is 29 x 19 cm
Nutrition Information:
Yield: 16 Serving Size: 1Amount Per Serving: Calories: 306Total Fat: 17gSaturated Fat: 11gTrans Fat: 1gUnsaturated Fat: 5gCholesterol: 46mgSodium: 153mgCarbohydrates: 33gFiber: 1gSugar: 28gProtein: 4g
Nutritional values are approximate. Please use your own calculations if you require a special diet.
Thank you for checking out this recipe. I hope you enjoy making and eating it! If you have any questions, queries or feedback, please feel free to leave a comment below.
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Vanya










Anne-Marie says
Can this be frozen (not just to cool it down)?
VJ cooks says
Yes, that should be fine.
Debbie says
I made this and followed the directions but there seemed to be way too much butter ?
VJ cooks says
Sorry to hear that, this recipe always works perfectly for me. It could be to do with the size of the cookie crumb, if it's too chunky the butter can't absorb as well.
Sharon Johns says
I made this today and put the biscuits in the food processor and they were really fine Do they need to be a little course????I only used 200g of butter also and it was too soft and sticky in the base
VJ cooks says
Hi Sharon, there needs to be a balance of fine crumbs and chunky pieces of biscuits for the butter to absorb quickly. I've amended the recipe to clearly state this. But if you look at the process pictures, you can see just how chunky some of the pieces are.
Peta says
Wondering if this could be made with left over Easter Eggs melted down?
VJ cooks says
Hey Peta, this recipe doesn't actually have any chocolate in it! You could use melted chocolate in place of the icing though.
Kirsty says
Would make again but with a few tweaks. I had the same issue with excess butter as others have had with the butter congealing to give an unpleasant look at the edges. Plus I found it just a bit too sweet. I think next time I will use 1/2C of cocoa to cut the sweetness and perhaps reduce the butter a smidge (though a bit of extra cocoa may help soak it all up). It was still gobbled up by all regardless.