Gluten Free Rhubarb Cake with Buttermilk

This Gluten Free Rhubarb Cake recipe is moist and made with buttermilk. It's made with lemon zest and baked with a cinnamon sugar topping.

For years my feelings toward rhubarb were lukewarm at best. Nowadays it seems like I can't enough of it. Especially when it means I get to enjoy things like this Rhubarb Cake.

This cake is based off a recipe found in my favorite old church cookbook. It's one of those old fashioned desserts that uses simple ingredients and requires no fancy cooking techniques.

This gluten free rhubarb cake is made with buttermilk so it's super moist. It's flavored with both lemon and orange zest which makes the cake fragrant.

The whole thing is topped off with a layer of cinnamon sugar which creates a light crust on top as it bakes. This cake will get you excited for rhubarb season!

Jump to:

• Can I Use Frozen Rhubarb In Place Of Fresh?
• Ingredients For Gluten Free Rhubarb Cake
• How To Make Rhubarb Cake From Scratch
• Combine The Wet and Dry Ingredients With Buttermilk
• Do I Need To Cook Rhubarb Before Baking?
• How Long Should I Bake Rhubarb Cake?
• What To Serve With Homemade Cake
• Does This Cake Need To Be Refrigerated?
• Can I Freeze Rhubarb Cake?
• Gluten Free Rhubarb Cake with Buttermilk

Can I Use Frozen Rhubarb In Place Of Fresh?

Every year during the early months of summer a small patch of rhubarb pops up at the edge of nearly every garden in the state of Minnesota.

It's ubiquitous in these parts and can be found in desserts lining the serving tables at potlucks and picnics during the summer months.

Rhubarb is always best when fresh as is the case with most produce. Given the short growing season many folks choose to freeze their rhubarb in order to preserve it throughout the colder months.

It's important to note that the only part of the plant that is edible are the stalks. The leaves contain oxalic acid and are poisonous so it's important to remove them if you are using fresh rhubarb!

The great thing about rhubarb is that it can be enjoyed fresh or frozen.

• If you choose to use frozen rhubarb in place of fresh simply place it in a strainer and thaw for a few hours before use.
• Once the rhubarb is thawed place it in between a few paper towels or kitchen towel in order to absorb any excess moisture.
• After the thawed rhubarb has been patted dry it may be chopped or used just as you would fresh.

Ingredients For Gluten Free Rhubarb Cake

As far as cakes go this one is easy to assemble. This recipe is gluten free and uses a gluten free flour blend but can be made with regular All-Purpose flour if gluten is not an issue for you.

Here's what you'll need to make it.

• 1 ½ packed cups Brown Sugar
• ½ cup (1 stick) Unsalted Butter (softened)
• 1 cup Buttermilk
• 2 Eggs
• ½ tsp. Kosher Salt
• 1 tsp. Baking Soda
• 2 cups Chopped Rhubarb (fresh or frozen)
• 2 cups Gluten Free Flour Blend (or regular AP flour if not gluten free)
• 1 Lemon (zest only)
• 1 Orange (zest only)
• ¼ cup Sugar
• 1 tsp. Cinnamon

It's best to use unsalted butter when baking. This allows you to control the amount of salt in your recipe and won't change the overall flavor profile of the cake.

The butter used to make this cake should be softened, but not melted. Feel free to let it sit at room temperature for a few hours to soften.

How To Make Rhubarb Cake From Scratch

This cake is made by combining the wet and dry ingredients in separate bowls and then combining them with buttermilk.

The chopped rhubarb is added once the batter has been combined.

1. Finely chop 2 cups of fresh (or frozen and thawed) rhubarb. Set aside.
2. Cream 1 ½ packed cups brown sugar and ½ cup (1 stick) softened unsalted butter using a stand mixer or hand mixer on medium speed for 1-2 minutes.
3. Once the butter and sugar are creamed together add 2 eggs and mix for another 30 seconds or so on medium speed (the mixture will be kind of sticky).
4. In a separate bowl add 2 cups gluten free flour blend (or regular AP flour if not gluten free), 1 tsp. baking soda, and ½ tsp. kosher salt. Stir until combined.

Combine The Wet and Dry Ingredients With Buttermilk

Once the wet and dry ingredients are ready it's time to combine them along with the buttermilk.

It's best to add the dry ingredients to the wet and do this alternately with the buttermilk so everything is combined evenly.

1. Add half of the dry ingredients to the wet and stir until combined. Add ½ cup of buttermilk to the batter and stir until combined.
2. Repeat with the second half of the dry ingredients and then the other half of the buttermilk.
3. Stir the batter just until combined.

It's important not to over-mix the batter or it may become tough (this is especially true if using All-Purpose flour.

Do I Need To Cook Rhubarb Before Baking?

There is no need to do anything special with the rhubarb other than to chop it before adding to the cake batter.

1. Once the batter is combined add 2 cups of finely chopped rhubarb.
2. Using a Microplane or small zester add the zest of 1 lemon and 1 orange.
3. Fold the rhubarb and zest into the batter just until combined.

The lemon and orange zest add a slight citrus note to the cake and make the whole thing a bit more fragrant.

You can use only lemon, only orange, or a combination of both.

How Long Should I Bake Rhubarb Cake?

Once the batter is ready it's time to place it in a cake pan and get ready to bake.

This recipe uses a 9x13 inch cake pan. You can use a glass or metal cake pan to bake this cake.

1. Heat oven to 350 degrees Fahrenheit.
2. Grease a 9x13 inch cake pan with butter or cooking spray.
3. Spread the batter evenly across the bottom of the pan (the batter will be kind of sticky).
4. In a small bowl combine ¼ cup sugar and 1 tsp. cinnamon.
5. Sprinkle the cinnamon sugar mixture evenly over the top of the cake.
6. Place the cake in the oven and bake for 38-40 minutes.

Baking times may vary slightly depending on the type of cake pan and oven used. I found 40 minutes to be perfect but baking times may be different for you.

To test if the cake is done place a toothpick in the center. If the toothpick is clean when removed then the cake is ready.

The top of the cake should be golden brown when finished.

It's best to use glass baking pans, metal pans with a protective coating, or a nonreactive pan, as rhubarb is acidic and can cause discoloration to metal cookware.

What To Serve With Homemade Cake

After the cake has finished baking remove it from the oven and allow to cool before serving.

This Rhubarb Cake is great because you can serve it for dessert after dinner or for breakfast with coffee.

The texture is moist and springy. It's somewhere between a coffee cake and a sponge cake.

The sugar helps to balance out the tartness of the rhubarb, the citrus adds a floral note, and the cinnamon sugar topping creates a light crust as it bakes.

I love it as-is but you can top it with some whipped cream or ice cream to make it more decadent.

For a healthier topping you can opt for yogurt or Greek yogurt.

Feel free to garnish with some nuts like almonds or granola for extra crunch.

Does This Cake Need To Be Refrigerated?

To store rhubarb cake all you need to do is allow it to come to room temperature and cover the cake pan with a tightly fitted lid or a dish towel so that it doesn't dry out.

It should last for 3-4 days stored covered on the counter at room temperature.

You can store it in the refrigerator for 3-4 days if you prefer. Make sure the cake is stored in an airtight container so that it doesn't dry out.

Love old fashioned desserts? Don't miss these recipes!

• Old Fashioned Blueberry Buckle
• Scandinavian Almond Cake
• Baked Lemon Doughnuts
• Coffee Infused Banana Bread
• Pumpkin Streusel Coffee Cake
• Gluten Free Apple Muffins

Can I Freeze Rhubarb Cake?

Yes! This cake can be frozen.

How To Freeze

1. Allow the cake to cool completely before freezing.
2. Wrap the cake tightly in plastic wrap or some kind of cling wrap. Then, place the wrapped cake in a heavy-duty freezer bag or tightly wrap it in foil.
3. Label with the date and store up to 3 months.

How To Thaw

1. Place the cake in the fridge 12 hours before serving.
2. You can also thaw it on the counter top for a few hours if preferred.

If you like this Rhubarb Cake I think you'll love this Cinnamon Sugar Apple Cake!

Love desserts? Check out these recipes!

• Italian Chocolate Hazelnut Cake
• Pumpkin Bread Pudding
• Bailey's Irish Cream Doughnuts
• Maple Pumpkin Scones
• Pistachio Panna Cotta

If you like this Rhubarb Cake you'll love these Rhubarb Muffins and Rhubarb Streusel Bread!

Love Rhubarb? Don't Miss These Recipes!

Baked Sticky Rhubarb Pudding

Rhubarb Crisp

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