These Gluten-Free Vegan Lemon Crumble Bars are the perfect sweet treat: a crunchy base topped a creamy, tangy lemon curd and a "buttery" crumble topping. They're refined sugar free and are an excellent make-ahead for Easter, Mother's Day, bridal showers and baby showers! They're great for sharing and an excellent alternative to Lemon Pie!

A lemon crumble bar on a marble slab against a brown background

Why does this recipe use brown rice flour?

You can use white rice flour or gluten-free flour, but I found the texture was much better with brown rice flour. If you can't find brown rice flour in your local supermarket, you'll be able to find it in local health stores or online.

How is the lemon curd made?

The lemon curd is made using shop-bought custard powder.

This is my favourite custard powder - it's vegan, gluten-free and sugar-free, and contains just 4 simple ingredients!

Not only does this custard powder act as a thickener, making the lemon curd extra creamy, but it also adds a lovely colour without having to use something like turmeric.

What can the custard powder be replaced with?

If you can't get hold of a shop-bought custard powder, you can replace it with the same amount of cornflour (cornstarch) or arrowroot, which will result in a similar texture, though the colour will be considerably less yellow.

To add yellow colour, I would suggest adding a tiny pinch of saffron, which I much prefer to turmeric as it has a much milder flavour.

What type of plant-based milk is used to make the lemon curd?

You can use any type of plant-based milk, though results do vary depending on which one you choose: cashew, oat or coconut milk make the creamiest and thickest curd, whilst almond milk will be less creamy. I personally prefer to use rice milk as it creates a just-set lemon curd-like consistency which I love.

How to make this recipe

Scroll down to the bottom of the post for the full recipe.

Mix together the ingredients for the dough in a glass mixing bowl.

Transfer one half into a square baking tin.

Tip: Line the tin with greased baking paper to make it easier to remove the bars after.

Use your fingers to push the mixture all the way to the edges, then use a spatula to press down on it until the surface is completely even.

Raw crumble bar dough along the bottom of a square baking tin

Bake in oven for 10 minutes - you'll be baking this again so you don't want to over-bake at this stage!

Measure out the rice milk in a measuring jug.
Pour the milk into a pan, leaving behind a few tablespoons of milk in the jug.
Heat up the milk.
Add the custard powder to the remaining milk in the jug and mix well, ensuring it has dissolved completely.
Once the milk in the pan is steaming, add approximately half of the hot milk to the bowl with the dissolved custard powder, mix well and transfer the custard powder mixture to the pan.
Mix well and keep stirring on a low heat for around 5 minutes, until thickened.
Add the lemon juice and maple syrup.

Pour the lemon curd over the base until it’s completely evenly covered and make sure the surface is smooth.

Tip: Tap the dish gently on the counter a few times to get rid of the air bubbles.

Lemon curd on top of crumble bar base in a square baking tin

Use your fingers to crumble the rest of the dough mixture over the top until it is all used up and the lemon curd completely covered.

Crumble bar dough sprinkled over lemon curd in a square baking tin

Bake in the oven for around 20 minutes, or until golden brown.

Baked lemon crumble bars in a square baking tin

Leave to cool then keep in the fridge for at least 4 hours until it firms up - may take slightly longer depending on the type of custard powder you use, the temperature of your fridge etc.
Cut into squares once it’s completely firmed up.

How long do these keep for?

These Lemon Crumble Bars do taste best when fresh, but they keep covered in the fridge for up to a few days.

Substitutions you can make

you can replace the coconut oil with coconut butter
you can use any type of liquid sweetener: maple syrup, agave syrup, brown rice syrup etc
the ground almonds (almond meal) can be replaced with ground walnuts
for a nut-free version, use ground sunflower seeds instead of ground almonds and use a nut-free plant-based milk
you can replace the brown rice flour with plain flour if you’re not gluten-free
you can add flaked or desiccated coconut or oats to the crumble topping.

Substitutions to be careful of

you can use white rice flour or gluten-free flour but the texture is much better with brown rice flour
I would recommend making the curd with rice milk - see recipe notes for details.

Three lemon crumble bars on a marble background

More vegan dessert recipes

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Gluten-Free Vegan Lemon Crumble Bars