Packed with rich, buttered rum flavor, this Buttered Rum Cake is going to make your keto holiday! Just like a traditional rum cake, the flavor of this cake improves as it sits for a day or two, so make it ahead of time for your holiday gathering. Served up with a dollop of fresh whipped cream and maybe an extra drizzle of glaze, I guarantee this cake will knock your Christmas socks off!! Keto, Low Carb & Gluten Free
Preheat oven to 350 degrees. Grease or spray a 8-9" loaf pan and line with parchment or spray and prepare your bundt pan. See notes for baking tips.
In a small skillet on low-medium heat, like a 3-4 setting, melt butter. Continue to cook the butter about 7-10 minutes, stirring often until the butter is browned and nutty. The solids in the butter should be the color of caramel. Remove from heat and set aside to cool.
Using a stand mixer and a whisk attachment, whip eggs until light, foamy triple in volume. This can also be done with a handheld mixer but use a large bowl to prevent splatter!
If using a stand mixer, switch to paddle attachment. Add sweetener and mix. Add almond and coconut flours, salt, baking powder and baking soda to egg mixture and mix on medium speed till combined, scraping down sides at least once. Add sour cream, browned butter, and vanilla and rum to the batter and mix again till combined.
Be sure to measure out your almond flour and coconut flour correctly, to much and you will have a drier cake. Fluff the flours up and spoon loosely into the measuring cup and level off without packing it down.
Depending on what pan you decide to bake this cake in, your baking time will vary. I prefer a loaf or bundt style pan. I used a smaller bundt pan that had a 10 cup capacity, so will hold about 6 cups of batter mix and after it baked it did not bake high enough to fill the whole pan but still looked great! If you use a larger 12 cup capacity, you may want to prepare double the recipe...I have not tested this recipe in a bundt pan that size.
You can also use mini bunt pans for this. I tested this recipe using a tin with 12 mini bundts and they took about 12-15 minutes to cook. You should fill them about 2/3 to 3-4 full. You will have to remove them from the pan to glaze them which will result in a less soaked cake.