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I'm so excited to share this easy Keto Rhubarb Custard Pie recipe.

Rhubarb, rhubarb, rhubarb! This year this vegetable has been my main focus for keto summer desserts. Yes, it actually is considered a vegetable!

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But since it's so often used in sweet desserts, I can't help but think of it as a fruit. It's either sweetened on it's own in recipes or can be combined with strawberries most commonly or other berries!

Now, the leaves of rhubarb are known to be “poisonous” but really they are just high in oxalates meaning they can cause stomach upset if some is consumed.

If you consume a LOT than kidney stones or kidney failure COULD be a possibility. But the stems of rhubarb are completely safe to eat.

I grew up with rhubarb in our garden, we had loads of it and we had this kind neighbour who would come and take some ever year for recipes and would always leave us a large bag of chocolates and candy on our door knob to say thank you.

We always had rhubarb muffins and rhubarb crisp almost every year without fail (click the links to see my keto versions of each). Those were our go-to desserts.

But one year I wanted to make my own rhubarb dessert and simply mixed rhubarb with some sugar and cinnamon and cooked it down.

It was honestly quite tasty even on it's own! That's kind of where the inspiration for this Keto Rhubarb Custard Pie came from.

If you've ever had rhubarb before, you know it's not very good by itself. It's like a slightly softer version of celery with a super tangy, sour flavour.

But this flavour pairs extremely well with sweet desserts just as lemon often does. The sweetness from sugar or a sweetener and the tangy rhubarb flavour is a perfect combination.

Rhubarb also softens up more as it bakes so you don't get any crunchy bites, it's just like baking with any other fruit.

This Keto Rhubarb Custard Pie is honestly one of my favourite keto rhubarb desserts to-date.

Why? Well, because for one it's super tasty and truly showcases the rhubarb. It's a great way to use up a lot at once.

And secondly, it's just so easy to make! It does not require much effort and this pie is completely keto friendly and low carb. It's a great way to impress family and friends with a seasonal dessert.

The crust is made up of a simple almond flour and coconut flour blend for the best flavour and texture while the filling is mainly just eggs, heavy cream and rhubarb!

It's amazing something so simple can taste so good. Each bite is filling with the rich, creamy custard, cinnamon almond flour crust and tangy bites of rhubarb. This is a dessert even picky eaters will love.

I hope you enjoy this Keto Rhubarb Custard Pie as much as we did!

Keto Rhubarb Custard Pie Ingredients

Almond Flour – This provides the best base for our crust and helps give it a more traditional pie crust flavour.
Coconut Flour – This flour is added to the crust and filling. In both cases it's used as a thickener. Coconut flour is extremely absorbent. It also improves the flavour of any almond flour keto baked goods when a small amount is added.
Powdered Monkfruit Sweetener – This is my favourite keto sweetener! Since it's powdered, you don't get the same grittiness in the pie once it cools as you would with a granulated sweetener. For this specific recipe I HIGHLY recommend this sweetener rather than one that's granulated.
Cinnamon – This is optional, but I love the combination of cinnamon and rhubarb!
Butter – This is only needed in the crust and can be replaced with coconut oil for a dairy free option.
Eggs – Allow your eggs to come to room temperature prior to baking for best results.
Heavy Cream – You can replace this with full fat canned coconut milk if you'd like a dairy free option.
Xanthan Gum – This is a thickener! A small amount goes a long way in thickening sauces. It also helps to provide a slight chew to the crust, similar to how gluten would in regular crusts.
Rhubarb – I used fresh raw rhubarb that I diced but you are welcome to use frozen rhubarb instead.

Tools I Used To Make Keto Rhubarb Custard Pie

The Ultimate Low Carb Substitution Guide
9-Inch Pie Pan
Whisk
Mixing Bowls

Tips For Making Keto Rhubarb Custard Pie

Tent your pie part-way through baking to prevent over-browning of the crust.
Only add filling up to the edge of the pie crust. If you have any extra, you can pour it into small ramekins and bake it crustless. Top it with a simple almond flour crumble or eat it on it's own!
Make sure to let your pie FULLY set before slicing or you'll have a big mess! You can place it in the fridge to speed the process up but this pie is best eaten at room temperature or warmed. (I just heat slices for ~20-30s in the microwave).

How To Store Keto Rhubarb Custard Pie

Store this pie in the fridge for up to 5 days OR freeze slices in an airtight container with a piece of parchment or wax paper on top to prevent freezer burn.

Other Keto Rhubarb Recipes You May Like:

Keto Rhubarb Custard Pie Recipe

Serves: 8 slices

Ingredients:

Crust:

1 cup almond flour, 112g
3 tbsp coconut flour, 21g
3 tbsp powdered monkfruit sweetener, 36g
1/4 tsp cinnamon
1/2 tsp xanthan gum, optional
1/8 tsp salt
1/4 cup melted butter, 60g
1 whisked egg
1/4 tsp vanilla extract

Rhubarb Pie Filling:

2 eggs
2/3 cup heavy cream, 160ml
2/3 cup powdered monkfruit sweetener, 135g
1/2 tsp vanilla extract
1 1/2 tbsp coconut flour, 10g
1/4 tsp xanthan gum (or another 2 tsp coconut flour)
1/4 tsp cinnamon
pinch of salt
1 1/2 cups diced rhubarb, 170g – 200g

Directions:

Pre-heat the oven to 325*F.
Add the almond flour, coconut flour, 3 tbsp powdered monkfruit sweetener, cinnamon, xanthan gum and salt to a medium bowl. Whisk to combine.
Add the melted butter and whisked eggs and mix again until you get a thick, slightly crumbly dough.
Butter a 9 – inch pie pan and then press the mixture into the bottom of it, going up the edges slightly.
Use a fork to poke holes all over the crust to prevent it from rising at it bakes.
Bake the crust for 10 minutes.
Meanwhile, make the filling by whisking together the 2 eggs in a large bowl.
Add the heavy cream, sweetener, vanilla extract, coconut flour, xanthan gum, cinnamon and salt. Whisk again until everything is very well combined.
Once your crust is finished baking, pour the diced rhubarb into it and spread it out evenly.
Then pour your filling on top of the rhubarb. Only pour until you reach the top edge of the pie crust. If you have any extra filling you can save it and bake it on it's own with diced rhubarb as a mini custard!
Bake the pie on the middle oven rack for roughly 33min. Gently tent the pie with tinfoil part way through if you notice the crust browning too quickly.
Let the pie cool completely at room temperature before attempting to slice. (Sometimes I refrigerate it on a towel to cool it faster then heat slices a little in the microwave before serving). Enjoy your Keto Rhubarb Custard Pie!

Nutrition for 1/8th of pie: 255 calories | 23.1g fat | 2.5g NET carbs | 6.1g protein | 3.8g fiber

Store this pie in the fridge for up to 5 days OR freeze slices in an airtight container with a piece of parchment or wax paper on top to prevent freezer burn.

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3.57 from 16 votes