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No recipe blog these days is complete without a chocolate cake in a mug/bowl/what-have-you. So here’s mine. Shall I sell you on it? Well, it only takes 5 ingredients (plus water, but I thought I could have that one for free), a minute in the microwave, and it’s perfectly chocolatey and fluffy(!) and moist. What more could you ask for? Guaranteed to cure chocolate cravings. Bam.
This chocolate cake is very good by itself; but as you can see, I have my own toppings I like to put on it. Since there’s not a lot of fat in the cake itself, I feel free to add a little natural peanut butter on top (not nut free, obviously – but the cake is!), garnish with a small squirt of fat-free Reddi-Whip, and douse the whole thing with unsweetened almond milk. I just have a thing for milk on cakey stuff. I was the kid who stirred her cake and ice cream together into one big soggy goulash at parties.
Trim Healthy Mamas (click here for my quick synopsis of the plan), I love the Cake in a Mug recipe from the book. However, it does tend to be a little on the dry side for my tastes, so this was my solution. And while my cake only takes 5 ingredients, which is cool, it doesn’t have the coconut oil that the recipe from the book includes. Coconut oil is your friend, so don’t give that recipe up, OK? Also, if you’re doing a Fuel Cycle, the Cake in a Mug from the book is suitable for the Deep S days, whereas this recipe is not because of the sour cream.
Want to see more 5-ingredient recipes? Click here!
Question of the day: would you like a chocolate or vanilla cake?
P.S. – I’m working on a vanilla version of this in time for strawberry shortcake season…(update: see it here!)
You can pin this post from my Desserts board here.
You can find this recipe in my cookbook, Necessary Food.

- 1 egg
- 1 T water
- 1 T sour cream
- 2 level T cocoa powder
- Sweetener of choice, to taste (see the Notes section below for what I used)
- ½ tsp. baking powder
- Toppings of choice, optional (see Notes section)
- Combine all ingredients until totally smooth and microwave in a small glass bowl for 1 minute or until mostly done through but still a little wet on top in the middle. I used a 2 cup glass Pyrex dish which worked wonderfully.
Since this chocolate cake is pretty light in the fat department, I like to add a little on top! My favorite topping is some natural peanut butter (not nut free, obviously), a small squirt of FF Reddi-Whip, and some unsweetened almond milk (also not nut free).
Suggested products:
THM Pure Stevia Extract Powder can be purchased from the Trim Healthy Mama online store. Truvia can be purchased here.
Will this be ruined if I add lilys chocolate chips to it?
Ruined by adding chocolate chips? Definitely not. 😉
So yummy! I needed something “sweet” and this hit the spot! Thank you so much for sharing your amazing recipes with us!!!!
I have your cookbooks and love your recipes, but could you please give nutrition facts with each recipe?
Hi Carol! I didn’t originally offer nutritional information with my recipes because Trim Healthy Mama, the healthy eating lifestyle I follow, doesn’t require it, but I’ve recently been adding it to my new blog recipes. 🙂 Eventually I may find time to go through my old blog recipes and add it to them too, but I’m not sure when that will happen. 🙂 MyFitnessPal is a super easy way to find nutrition facts! If you sign up for an account, under the Recipes tab there’s a place where you can just add the link to a recipe and it will pull up the ingredients for you to confirm, then generate the nutritional info! 🙂
Has anyone tried this with some 0% plain Greek yogurt in place of sour cream? I can’t wait to try this!! Thanks. 🙂
I do that often – should be just fine!
My first attempt at making a THM type dessert and it’s pretty good! the amount of sweetener I used wasn’t quite enough, but tasted great topped with som peanut butter! Thanks Briana! I can’t wait to try more of your recipes.
I’m in Canada and don’t have fat free redi whip. Is a little whip cream ok? I’m assuming it’s just to keep fat content lower but want to make sure I’m not missing something! Thanks!
Yes, that’s fine!
Would appreciate receiving your new posts. Thanks
Hi Nancy! It looks like you signed up!
Love all the 5-ingredient recipes!
Wonderful! I added just a bit less than a pinch of salt and a dash of butter flavoring. Granted, now it’s a 7 ingredient cake but oh well! Love all your recipes but I love my salt and my butter. 😉
Hi Briana! This looks delish, but I only have truvia–how much would I use then? Just bump it to 2 tsp, or would that not add enough sweetness?
You can use this sweetener conversion chart to help you: http://www.trimhealthymama.com/main-home/sweetener-conversion-chart/
I would try starting with 2.5 tsp. of Truvia and add more if it doesn’t taste sweet enough to you. Always taste as you go and you can’t go wrong!
This is very good. Wondering if you know how to increase to a one layer 8 or 9″?
I would multiply the recipe by 5 or 6 depending on how thick you want your cake to be. Bake at 350 degrees F until a toothpick inserted in the center comes out clean.
Very delicious! Thank you
This is the best chocolate mug cake I’ve ever had! I cook it in a 2 cup Corningware French White Roubd Casserole; sometimes I make two for a cute little layer cake. Tonight I adapted it to make a Mocha Cake and it’s very good!
1 egg
1 T strong coffee
1 T sour cream
1 tsp Sugar Free Caramel Torani Syrup
1 tsp instant coffee
2 level T cocoa powder
Sweetener of choice, to taste (I used 2 T Swerve)
½ tsp. baking powder
I’ve ordered some coffee extract and will try this again when it comes but it’s very good without it!
Thanks for sharing!
coffee, chocolate and caramel….you can’t go wrong with that! Thanks, I WILL be trying this.
I just made this. I put walden farms sugar free maple syrup and chopped pecans on top. Very yummy. My 3 year old even kept stealing some from me, and my husband (not a dark chocolate fan) even gave the thumbs up on this!
I tried these tonight! I like it but have a question. The (t) is for tblsp or tsp? Also I find that when I’m doing chocolate recipes it almost seems bitter to me. Am I doing something wrong? I love your recipes appreciate your help with tasty healthy food! God Bless <3
A capital T (T) stands for “tablespoon” while “tsp.” means “teaspoon”. What are you using to sweeten your chocolate recipes? As I said in the recipe, I don’t recommend using only stevia to sweeten chocolate recipes; I like to use a blend of stevia and a granulated sweetener such as Truvia, or just the granulated sweetener (you’ll need a larger amount, obviously). For some reason, using only stevia tends to make chocolate recipes bitter.
I’ve had trouble with the cholate tasting bitter too, I just purchased the Thm sweet blend is that okay and how much would I use? Also for the Fudgy Mocha icing would that be okay to use sweet blend?
Yes, the Sweet Blend would be great to use in this as well as the frosting recipe (just grind it first if using it in frosting so your frosting isn’t gritty). You can use this sweetener conversion charts to help you figure out amounts: http://www.trimhealthymama.com/main-home/sweetener-conversion-chart/ Or you could always just add and taste as you go. That’s how I do it. 😉
Vanilla tops chocolate every time. 🙂
Lucky for you, the vanilla version of this came is coming out tomorrow! Stay tuned…
Delicious! Thanks so much for posting this. They were perfect, I added sliced strawberries and a sprinkle of powdered Swerve on top.
These are delicious and really hit the spot. I don’t have a microwave so I baked mine in a muffin tin for 10 min. at 350 using convection heat. Absolutely perfect, I loved the texture and I did as you and topped it with natural PB and redid whip. SO YUM!!!! Again, I LOVE your recipes, thank you!!!
Thanks so much for letting me know how long you baked it! I’m glad you enjoyed it.