A classic no-bake Thermomix Lemon Slice with a crushed biscuit, coconut and sweetened condensed milk base, then topped with a creamy, zesty lemon frosting.
Just 10 minutes prep time and 7 basic ingredients is all it takes to make this simple old fashioned family favourite slice.
When it comes to old fashioned slices, Thermomix Lemon Slice is right up there... along with Jelly Slice, Peppermint Slice and Passionfruit Slice.
These simple and popular classic slices have certainly stood the test of time - and now they're even easier to make with the help of your Thermomix!
In just 10 minutes, you'll have this entire slice (base and frosting!) prepped and into the fridge to set. It really is that quick and easy.
And because it's all made in your Thermomix, you'll have hardly any washing up to do afterwards too!
Why You're Going To Love This Recipe
This simple Thermomix Lemon Slice is one of my most popular recipes... here's why:
- Classic old fashioned favourite - a much loved recipe that has certainly stood the test of time. This is just like the lemon slice recipe your grandma used to make.
- Quick & easy - it takes just 10 minutes to prepare this slice! The hardest part is waiting for it to chill in the fridge.
- Basic ingredients - there's no need to make an extra trip to the supermarket! Thermomix Lemon Slice is made using a few pantry and fridge staples.
- Loved by kids & adults - this tasty lemon slice is popular with everyone right through from toddlers to grandparents! The sweet and zesty flavour combined with the creamy frosting is simply delicious.
- Freezer friendly - yes, thats right! Pop any leftovers in an airtight container and freeze for up to 3 months. Place directly into lunch boxes frozen or defrost in the fridge.
- Nut-free for school lunch boxes - this slice is the perfect option for school lunchboxes as it contains NO nuts (coconut is not considered a nut at schools).
Equipment Required
It couldn't be easier to make Lemon Slice using your Thermomix!
Let the Thermomix zest the lemon, crush the biscuits, mix together the base and whip up the delicious creamy lemon frosting for you!
- Thermomix - this recipe is suitable for use in all Thermomix models (TM31, TM5 and TM6)
- Spatula - to help with crushing the biscuits in the Thermomix and scraping down the sides of the bowl.
- Baking Tin - I recommend using an 18cm x 28cm rectangular slice tin lined with baking paper.
What You Need
Thermomix Lemon Slice is made using just a handful of basic ingredients:
Note: Scroll to the recipe card at the bottom for the ingredients quantities and full detailed method
For The Base
- Biscuits - known as cookies in the US. You can use any plain sweet biscuits you like for this recipe. I generally use Arnott's Marie biscuits which are popular here in Australia.
- Sweetened condensed milk - I recommend using full fat (not skim or light) sweetened condensed milk as it sets firmer.
- Butter - you can use either salted or unsalted butter in this recipe.
- Coconut - use desiccated coconut which is a fine, dry and unsweetened coconut.
- Lemon - both lemon zest and juice are used in the base. You can grate the lemon zest using your Thermomix - super handy!
For The Frosting
- Icing sugar - it's important to use pure icing sugar (not icing sugar mixture). This is because pure icing sugar sets firmer, giving the frosting the perfect texture. Icing sugar mixture is much softer and can result in a runny frosting (not good for school lunchboxes!)
- Butter - again, you can use either salted or unsalted butter.
- Lemon juice - this gives the frosting a delicious zesty flavour.
- Coconut - use dry desiccated coconut for sprinkling over the top of the frosting.
Step By Step Thermomix Instructions
It is SO quick and easy to make Lemon Slice in your Thermomix... just 10 minutes prep time and a couple of basic steps!
Note: Scroll to the recipe card at the bottom for the ingredients quantities and full detailed method
Step 1 - Grate The Lemon Zest
Peel the yellow part of the lemon skin with a peeler or knife. Place it into the Thermomix bowl.
Mix until finely grated.
TIP: You will need to scrape down the sides of the bowl a couple of times in between grating.
Step 2 - Crush The Biscuits
Add the biscuits to the bowl with the grated lemon rind. Mix on Speed 8 until fine crumbs remain. Set aside in a seperate bowl.
Step 3 - Melt The Butter
Add the butter to the Thermomix bowl.
Mix until completely melted.
Step 4 - Mix The Ingredients
Add the sweetened condensed milk, lemon juice and coconut and mix to combine.
Return the crushed biscuits to the bowl and mix to combine.
TIP: Scrape down the sides of the bowl partway through mixing.
Step 5 - Press Into Tin
Press the mixture very firmly into a prepared and lined rectangular slice tin.
Use the back of a spoon to smooth the surface.
Step 6 - Make The Frosting
Place all of the frosting ingredients (except for the coconut) into the Thermomix bowl.
Mix until smooth and creamy.
Spread the frosting smoothly over the base.
TIP: If your frosting is too thick, add a little extra lemon juice and mix again. If the frosting is too runny, add a little extra icing sugar and mix again.
Step 7 - Chill
Sprinkle desiccated coconut over the top of the frosting and place into the fridge for a minimum of 4 hours to set (overnight is best!)
FAQ'S
Absolutely! Either store-bought bottled lemon juice or fresh lemon juice are fine to use.
Sure can! You can find my lime slice recipe here.
Yes, you can - you can find my conventional lemon slice recipe here.
Firstly, ensure that you're using pure icing sugar and not icing mixture. Pure icing sugar is required as it sets firmer. If you find that your frosting is too runny, simply add a small amount of extra icing sugar and mix again. The frosting should be thick and creamy but spreadable. Note: the frosting will firm up once chilled.
Expert Tips
- Line your baking tin - line your slice tin with baking paper to allow for easy removal once the slice has been chilled and is ready to be cut into pieces.
- Use full fat sweetened condensed milk - this helps the slice to set firmer than skim or light sweetened condensed milk.
- Use pure icing not icing sugar mixture - pure icing sugar sets firmer and will ensure the frosting is a creamy, soft texture (but not runny!).
- Storing - Thermomix Lemon Slice can be stored in the fridge for up to 1 week.
- Freezing - freeze any leftovers for up to 3 months in an airtight container. Allow to defrost in the fridge before consuming. Alternatively, you can place frozen lemon slice directly into school lunchboxes and it will be defrosted by morning tea time.
More Thermomix Lemon Slice Recipes
If you love making lemon slices using your Thermomix, give these delicious recipes a try!
Thermomix Lemon Slice
Ingredients
For The Base
- lemon juice and zest from 1 lemon
- 80 g butter
- 250 g plain sweet biscuits (like Arnotts marie biscuits)
- 250 g sweetened condensed milk
- 90 g desiccated coconut
For The Frosting
- 360 g pure icing sugar
- 90 g butter softened to room temperature
- 60 g extra lemon juice
- 20 g desiccated coconut for sprinkling
Instructions
- Grease and line a rectangular 18cm x 28cm baking tray with baking paper and set aside.
- Peel the zest (yellow skin) off the lemon and place into the Thermomix bowl. Grate for 10 seconds, Speed 8. Scrape down the sides of the bowl. Repeat until finely grated.
- Add the biscuits and crush on Speed 8, 5 seconds. Scrape down the sides of the bowl and mix for a further 5 seconds or until fine crumbs remain. Set aside in a seperate bowl.
- Place the butter into the Thermomix bowl (with the lemon zest) and melt for 3 minutes, 60 degrees, Speed 3.
- Add the sweetened condensed milk, coconut and lemon juice into the Thermomix bowl and mix for 10 seconds, Speed 4. Scrape down the sides of the bowl and mix for a further 10 seconds, Speed 4 or until combined.
- Add the crushed biscuits/lemon rind back into the Thermomix bowl and mix for 10 seconds, Speed 6. TIP: Use the spatula to help mix. Scrape down the sides of the bowl halfway through mixing.
- Firmly press the mixture into the prepared tin and place into the fridge.
- Place the icing sugar, butter and lemon juice into the Thermomix bowl and mix for 20 seconds, Speed 4. Scrape down the sides of the bowl with the spatula. Mix for an extra 30 seconds on Speed 4. TIP: If the frosting is too thick to spread, add a little more lemon juice and mix again. If the frosting is too runny, add a little more icing sugar and mix again.
- Spread the frosting over the slice, sprinkle with the extra coconut and place back into the fridge to firm completely (approximately 4 hours - or overnight for best results).
- Store in an airtight container in the fridge for up to 1 week or freeze for up to 3 months.
Notes
- Line your baking tin - line your slice tin with baking paper to allow for easy removal once the slice has been chilled and is ready to be cut into pieces.
- Use full fat sweetened condensed milk - this helps the slice to set firmer than skim or light sweetened condensed milk.
- Use pure icing not icing sugar mixture - pure icing sugar sets firmer and will ensure the frosting is a creamy, soft texture (but not runny!).
- Storing - Thermomix Lemon Slice can be stored in the fridge for up to 1 week.
- Freezing - freeze any leftovers for up to 3 months in an airtight container. Allow to defrost in the fridge before consuming. Alternatively, you can place frozen lemon slice directly into school lunchboxes and it will be defrosted by morning tea.
Louise C
A firm fave here in our house. Thanks for a great recipe.
I usually cut it into small pieces and freeze it.
I have also replaced the lemon with orange before and it's equally delicious.
Lucy
Great idea!
Emma
Does the slice go weird when it's defrosted? I thought jelly doesn't freeze well
Lucy
Hi Emma, this slice doesn't have any jelly in it. It freezes and defrosts perfectly 🙂