All Recipes/ Breakfast/ Healthy Sweet Treats/ Kids Food/ Latest Posts/ Weekend Treats

Rhubarb Breakfast Cake (Gluten-free, sugar-free)

Disclosure: this cake started as a Peach Breakfast Cake but since my first attempt with peaches I made some improvements to the batter but I wasn’t able to find organic peaches anymore. One day I saw rhubarb in stores (it’s popular here in Denmark) and I felt it could be a good fit. And oh wow, that was perfect. So Rhubarb Breakfast Cake it is.

However, I know in many places peaches season started (oh Texas peaches!!), so feel free to replace rhubarb with peaches. In fact, what is so great about this cake is that it can be made with different fruits. I only tried peaches, apples and rhubarb, but I’m thinking cherries and plums will work really good.

The flours I used for this cake are chestnut, tigernut and coconut. I know chestnut is a bit of a pain to find in the US, but Amazon sells it, as well as It’s totally worth it. In Europe, chestnut flour is common in gluten free baking so it can be found more easily in supermarkets or speciality stores. It’s also less expensive, because the one you usually find in the US is imported from Italy – where chestnut flour is common and used in specific dessert recipes. I guess you are much more familiar with tigernut flour. In the US, I love Oragnic Gemini brand (no affiliation). Despite the name, tigernuts are not nuts, but small tubers. Both flours are very nutritious, albeit a bit carby. Again, in my world, totally worth it.

Rhubarb Breakfast Cake

Both flours are naturally sweet and very flavourful, so there is not much need for added sweetener or flavors. I did use one teaspoon of honey, but you can use yacon syrup or another sweetener of your choice. I call this a breakfast cake for a reason. It doesn’t have to be sweet. Other ingrediens are coconut milk, coconut flour and shredded coconut and hazelnut butter, so everything is tasty and sweet already. If you don’t find hazelnut butter, you can use pecan or any nut butter you have. Or even make your own.

If you ever tried rhubarb before you know it’s sour. So traditionally, a lot of sugar is added to rhubarb in desserts. In Denmark, rhubarb jam is very popular, but made with a lot of sugar. This cake to me is sweet and I feel it balances the sourness of rhubarb very well, but if you know yourself having a big sweet tooth, maybe you want to add some extra sweetener. You could possibly sprinkle so monk fruit on the rhubarb layer before you add the batter. Or, just leave it as it is and you can always drizzle some yacon or monk fruit syrup on top when serving if you feel is not sweet enough for you. Just remember, the whole point of eating sugar free is to re-educate your taste buds and brain to not want the sweet taste so much.

I won’t discuss substitutions because I really think this cake is so good because of the mix of flours used, but I had someone replacing the chestnut flour with hazelnut flour and they said it worked. I also had someone using almond flour and they say it didn’t. So feel free to experiment, but I can’t guarantee the same results.

The size of this cake is about 6, 7in diameter which makes about four portions. I use a ceramic tart dish. I can’t seem to find this size on Amazon right now, but it is the size in between the individual ones and the full size. Since this is an upside down cake, I would prefer to use smaller dishes, even individual ones, since the bigger the surface the bigger the risk to break it when you turn it upside down. So far I made this cake three times and I never have a problem while turning it. Just make sure you add a generous quantity of coconut oil to the dish before you add the fruits and the batter.

Now about measurements. Forgive me but now I’m in a camping type of living situation. We just relocated from Dallas to Denmark and although I have a fully equipped kitchen (thank God!), things are basic and more European. I don’t have measurement tools yet and I won’t buy any since I have mine coming in a container in about a month. The mesurment cup I have only has grams and I don’t feel like giving you measurments in grams in this case, as different gluten free flours tend to have different weights. So I went the old style (what my mom used to do) and use a soup / tea spoon, like the one you use to eat soup or the one to eat dessert or stir a tea. This recipe is pretty forgiving, and if you have more flour you can always add a little bit more coconut milk. I created this image to have an idea what I conside one tablespoon in this case.

Rhubarb Breakfast Cake (Gluten-free, sugar-free)

1 Star2 Stars3 Stars4 Stars5 Stars (8 votes, average: 4.75 out of 5)
By Claudia Curici Serves: 4
Prep Time: 10 minutes Cooking Time: 30 minutes

A delicious morning treat that is easy to make using a variety of seasonal fruits.


  • 1 tablespoon coconut oil, for greasing the dish
  • about 6 rhubarb sticks, chopped in 1/2 inch pieces (or more to fully cover the bottom of the dish)
  • 4 tablespoons chestnut flour
  • 4 tablespoons tigernut flour
  • 1 tablespoon coconut flour
  • 2 tablespoons shredded coconut
  • 3/4 teaspoon baking powder
  • pinch of salt
  • 1 big pastured egg
  • 2 tablespoons hazelnut butter
  • 1 teaspoon honey (or other sweetener of your choice), more if you have a big sweet tooth
  • 1 teaspoon vanilla extract
  • 12-15 tablespoons full fat coconut milk



Preheat the oven to 350F.


Prepare the dish by genrously coating it with coconut oil and arrange the rhubarb pieces on the bottom of the dish to fully cover it.


Mix the dry ingredients in a small bowl.


In a bigger bowl, mix the egg with the nut butter, honey and 10 tablespoons of the milk and mix well with a hand blender. Start adding the flour and incorporate it in the liquid. When you are done with adding the dry ingredients, you can add more of the coconut milk and blend well until you get a creamy batter that won't be easy to pour but it won't be too solid either. You can "pour" from the bowl in the dish with the help of a spoon. Level the batter and bake the cake on the middle rack for about 30 minutes.


Let it cool down for about 20 minutes before you turn it upside down, with the help of a plate. Check first the sides to see if there is any resistance. This cake should come out easily from the dish if the dish is well greased. Serve warm or cold, I love it both ways.


Please read the entire post before you start.

Gundry MD Ambassador Shop

You Might Also Like


  • Reply
    June 5, 2020 at 6:44 am

    I can’t find tigernut flour, what could I replace it with? Thank you x

    • Reply
      June 9, 2020 at 5:19 am

      It’s hard to make recommandations of substitutions when I have not tried it myself. Please read the paragraph about substitutions and see the two examples I gave, based on feedback from people who have tried to substitute. Best way is to experiement depending on what you have available. I would say almond flour would work, someone said they tried and failed… So I don’t know until I try it myself.

  • Reply
    December 29, 2020 at 11:15 am

    Made this as a Christmas morning treat with apples instead of rhubarb and it was absolutely delicious! I subbed hazelnut flour for chestnut flour and it worked well I think, though I did have to cook it a little bit longer than 30 minutes.

    • Reply
      December 29, 2020 at 11:45 am

      Thank you Greta! Good to know hazelnut flour works well. I think I’ll do the same for NYE. <3

    Leave a Reply