This Giant Donut Cake may be the pinnacle of my keto baking career! So fun and pretty, it makes a great cake for birthday parties. Low carb and sugar-free. This post is sponsored by Bob’s Red Mill.
I cannot lie to you, my faithful readers. This keto donut cake isn’t exactly the easiest dessert I’ve ever made. But it’s not exactly hard either. It has multiple steps to it and it takes time and effort, but nothing requires any special techniques. It’s really fun to make, and oh my word, is it spectacular!
If you are up for a bit of a keto baking challenge and you want to knock the socks off those keto naysayers, or you have a kid who is just dying for an impressive birthday cake, then this is the keto cake recipe for you. It really does look like a giant donut.
Don’t worry, I am going to walk you through every step. With photos!
I made this for my daughter’s 12th birthday party in December. I had seen a giant donut cake recipe on Pinterest and I saved it, thinking it would be a fun one to ketofy. When I showed it to my daughter, her eyes lit up and she agreed I could experiment for her birthday.
The conventional version was a white cake with a pink filling, but my darling girl wanted chocolate for the cake part. And she’s not much into pink these days but she let me do the pink frosting because it’s such a pretty contrast with the chocolate brown.
I had to think for a while on how to do this. I searched for the right kind of baking pan and I even ordered one that was specifically for donut cakes…except I knew the minute I saw it that it was much too small.
As I don’t want my readers to have to purchase specialized pans, I opted for my regular bundt pan. It does have some ridges but I knew I could cover those with a little chocolate frosting. Turned out perfectly!
Okay, ready for a full cake tutorial here? I tried to take photos along the way so you can see exactly how it’s done.
How to Make a Giant Donut Cake
The cake is just a regular chocolate bundt cake. To get really good consistency and texture, I recommend using a combination of Bob’s Red Mill almond flour and coconut flour. Together, they make a low carb cake with a fine crumb. Since I wanted the cake to hold together really well, I also used some Bob’s Red Mill xanthan gum.
The hardest part for a donut cake like this is the filling. But really, while it is multiple steps, it’s not difficult – it simply takes time. So I am going to go through these steps as carefully and as clearly as possible.
Once the cake is cool, you need to flip it upside down. The best way to do this is to cover the top with a cookie sheet and then get one hand underneath the bottom rack or plate and one hand firmly on the top plate. Then flip the whole thing upside down.
You need to create a trench for the low carb raspberry frosting, but you also need to save pieces of the trench to cover the filling. So you can’t just start digging into it. Take a sharp knife and cut into the cake at an angle all the way around the outside edge. Then do the same on the inside edge so you are taking out triangular shaped pieces. You only need to cut in by about an inch.
Cut it out by sections. Save these pieces because you will be using slicing off the very bottom to put back onto the cake once it’s filled.
Now take a spoon to dig out a nice trench about an inch and a half to 2 inches deep. Spoon in the filling, leaving a little space at the top so you can put more cake back in. You won’t use all of the raspberry frosting so set the remainder aside for the top of the cake.
Take each section of cake you cut out and slice off the very bottom and put it back over the filling.
None of this needs to be perfect. As long as the filling is covered with cake so that it doesn’t goo out once you flip it back over, you’re good. No one will be able to tell once that pretty cake is cut into slices.
Frosting a Keto Donut Cake
Because my cake was done in a bundt pan and wasn’t perfectly smooth, I decided to cover the whole thing in a layer of low carb chocolate buttercream. You don’t have to do this – I’ve seen other donut cakes with the bundt pan ridges showing. But it does add to the chocolate-y goodness!
For the final glaze, you use the remainder of the raspberry frosting and thin it out with water. It’s hard to say exactly how much water to use, but you want it to be pourable but still quite thick. So add one tablespoon of water at a time, whisking it in, until you have the right consistency.
Then spoon it over the top of the cake, pushing it over the sides with a spatula so it makes nice swoops and drizzles. Add a few colourful sprinkles, if desired.
And refrigerate that sucker for at least 2 hours!
Phew! Wasn’t that fun? Definitely some work but fun nonetheless. And now you’ve got a great keto donut cake with delicious chocolate frosting and raspberry filling.
Let’s get baking!
More Keto Birthday Cake Ideas!
Giant Donut Cake - Low Carb and Keto
- ¾ recipe best low carb chocolate buttercream
- Preheat oven to 325F and grease a large bundt pan (9 to 10 inches in diameter) well. I like to double grease (working butter into the pan first and then spraying with coconut oil or avocado oil spray).
- In a large bowl, whisk together almond flour, sweetener cocoa powder, coconut flour, whey protein, baking powder, salt, and xanthan gum
- Add the eggs, melted butter, vanilla extract and ⅔ cup of the water. Add the If your batter is very thick add additional water, 1 tablespoon at a time, until it thins out. It should be spreadable but not pourable.
- Spread batter in the prepared pan and smooth the top. Bake 45 minutes or until set and a tester inserted in the center comes out clean.
- Let cool in the pan 30 minutes, and then flip out onto a wire rack to cool completely.
- In a small saucepan over medium heat, bring the raspberries and water to a boil. Cook about 5 minutes, until the berries can easily be mashed. Strain through a sieve into a bowl, pressing on the solids to extract as much juice as possible.
- In a large bowl, beat the cream cheese, butter, and sweetener together until smooth. Beat in the raspberry juice and the extracts. If the frosting is stiff, beat in the heavy cream. DO NOT ADD THE WATER YET!
To Fill the Cake:
- Flip the cake over carefully onto a plate to cut a trench in the bottom. You will cut a trench about 1 ½ inches wide in the bottom of the cake, and about 1 ½ inches deep. Use a sharp knife to cut at an angle so that you can lift whole sections of the cake out intact (you will need pieces of it to cover the filling before flipping the cake back over).
- Use a spoon to scoop out more of the cake so that the trench is rounded at the bottom. In the end you want the trench to be about 1 ½ to 2 inches deep. Fill the trench with raspberry frosting, almost but not quite to the top (you will only need about a cup or so of frosting to fill the cake).
- Cut the very tops from the pieces you cut out and use those to cover the frosting in the trench. Press down to get it firmly in there. Then cover the bottom of the cake with a serving plate and flip the whole thing back over.
To Frost the Cake:
- Make the chocolate buttercream as directed and all over the entire cake, even inside the hole of the bundt.
- Whisk water 1 tablespoon at a time into the remaining raspberry frosting, until it is thick but pourable. Spoon it over the cake and let drip thickly down the sides. Add a few fun sprinkles and refrigerate at least 2 hours.