This Chocolate Crumb Cake recipe is the best of two delicious desserts combined into one. With a decadent moist chocolate cake layer, Crunchy chocolate crumble topping with added pockets of gooey chocolate chips. Amazing served warm with a scoop of cold ice cream or drizzled in chocolate fudge sauce.
Chocolate cake usually makes an appearance in my kitchen at least once a month, What can I say we do like dessert! Developing this chocolate crumble cake was the combination of adapting my recipe from my gluten free chocolate sheet cake and turning the crumble mixture that I have used in a few recipes like my apple and blueberry crumble into a chocolate crumble. As always I made it gluten free!
If you love sheet cakes then you have to check out my gluten free lemonade cake, gluten free old school cake, and gluten free banana cake they are great for taking along to parties.
⭐ Why we love this recipe
- Heavenly moist sheet cake with a crunchy topping
- Perfect party cake or indulgent dessert
- Chocolate lover's dream
- Gluten free but no one can tell!
- So easy to make
📋 Ingredients Notes
- Gluten free all purpose flour - AKA Plain flour in the UK. See baking tips for the flour blend I used when making the chocolate crumble cake.
- Cocoa powder - Using good quality cocoa powder will make all the difference in the outcome of the flavor of the chocolate crumb cake. Dutch-processed cocoa powder is what I recommend.
- Xanthan Gum - Prevents ingredients from separating as it is a stabilizer. Essentially acting as gluten would gel everything together. You can omit it if your flour blend already contains xanthan gum.
- Butter - For the crumble use cold butter straight from the fridge. For the cake, I find it easiest to melt the butter in the microwave.
- Chocolate chips - I love double chocolate and used milk chocolate chips but dark chocolate chips will also be delicious. See my gluten free chocolate information if you are unsure what chocolate is gluten-free.
- Sugar - Makes the cake light, gives moisture, and adds sweetness to the cake. I used white sugar in the chocolate cake batter and brown sugar in the chocolate crumble mix. If you only have white sugar available you can substitute the brown sugar for white sugar in the crumb topping.
- Baking powder & Baking soda - AKA bicarbonate of soda. Acts as a leavening and rising agent by reacting to heat. Making the cake light and rise well.
- Salt - Helps balance out the sweetness and enhances the flavor of the chocolate cake.
- Eggs - Room temperature
- Whole Milk - I like to take the milk out of the refrigerator 30 minutes before making the cake to allow the milk to come to room temperature.
- Hot water - Don't skip this step as adding hot water will add moisture to the chocolate crumb cake and prevent it from becoming too dry.
See the recipe card for quantities.
⚡ Substitutions & Variations
- Chocolate Coffee Crumb cake - add a shot of coffee in place of the hot water to add further depth to the chocolate flavor and make a chocolate coffee cake.
- Double chocolate crumb cake - add a mix of dark and chocolate chips because who doesn't love double the chocolate!
- Chocolate fudge drizzle - why not go all in with the ultimate chocolate experience and add a drizzle of hot chocolate fudge sauce and serve with cold ice cream. You can use store-bought fudge sauce or make your own as I have previously used in my Billy miner pie recipe.
🥣 Step by Step Instructions
Below is a brief step-by-step process with photos of how to make Chocolate crumb cake. See the recipe card below for more detailed recipe instructions.
Step 1.In a large bowl mix together the flour, cocoa powder, and xanthan gum. Mix in the sugar, and half the chocolate chips until evenly combined then place in the fridge to chill while you make the filling.
Step 2. In a large bowl mix together flour, sugar, baking powder, baking soda, cocoa powder, xanthan gum, and salt. In a separate bowl combine the eggs, milk, melted butter, and hot water. Mix well.
Step 3. Add the wet ingredients into the larger bowl that contains the dry ingredient mix and whisk until fully combined and resembles a smooth chocolate cake batter. Pour the chocolate cake batter into the prepared baking tin and spread it evenly within the tin.
Step 4. With the remaining chocolate chips sprinkle evenly over the top of the chocolate cake batter.
Step 5. Remove the crumble mixture from the fridge and spoon the chocolate crumb topping over the chocolate cake layer. Place chocolate crumb cake in the oven and bake for 40-50 minutes.
Step 6. You can check if the chocolate crumb cake is ready by inserting a wooden skewer and when it comes out clean with only a few crumbs on the skewer it is ready to remove from the oven.
See the recipe card for more detailed instructions.
This chocolate crumb cake recipe doesn't require any specialist kitchen equipment. A hand held whisk, two large bowls and a baking tin. I used a 9x13 baking tin You could use an 9x9 baking tin but will take slightly longer to bake.
💭 Gluten Free Baking
- Gluten Free Flour – I used a shop-bought Gluten free flour blend from Doves Farm Freee from range. Which is a flour blend of Rice, Potato, Tapioca, Maize, and Buckwheat flour. I have had reports that others have used Bob’s Red Mill and other Gluten free All purpose blends with my recipes that have worked well. I would love to know what flour blends worked for you so feel free to get in touch by leaving a comment below or you can contact me directly.
- Kitchen Scales - Using digital scales is recommended when baking. I always measure using scales and grams as baking is a science. When baking gluten-free it is essential to weigh out ingredients to get the best results! There is no need to purchase expensive digital scales and you can find them available cheaply online. (Although for small amounts I will use spoon measurements)
- Oven Temperatures - Your oven temperature may be slightly different. As all ovens vary in temperature and the baking time is used as a guide. Some ovens run hotter than others. You could invest in an oven thermometer to be more accurate.
Yes, The cake can be stored in an airtight container for you to enjoy for up to 3-4 days.
Yes of course. I often reheat a slice in the microwave for a few seconds and then top the warm cake with a scoop of cold ice cream, Delicious!
Yes, This recipe is gluten free! Just be sure all ingredients used are safe and don't have any may contain gluten warning on the ingredients labels.
🍫 More Chocolate Recipes
If you tried this Chocolate crumb cake recipe. Please leave a star 🌟🌟🌟🌟🌟rating in the recipe card below & a review in the comments section further down the page or tag me on Instagram.
Chocolate Crumb Cake
Nutritional information is meant as a guideline and all information is approximate.
- 9x13 baking tin You could use an 9x9 baking tin but will take slightly longer to bake.
Ingredients for the chocolate crumble layer
- 150 grams Gluten free all purpose flour AKA Plain flour in the UK
- 4 tablespoons Cocoa powder
- ¼ teaspoon Xanthan Gum You can omit if your flour blend already contains xanthan gum.
- 75 grams Butter
- 50 grams Brown sugar
- 100 grams Chocolate chips
Ingredients for the chocolate cake layer
- 200 grams Gluten free all purpose flour AKA Plain flour in UK
- 200 grams Sugar
- 50 grams Cocoa powder
- 1 teaspoon Baking powder Some brands may have ingredients that contain gluten. Always be sure to check the label.
- 1 teaspoon Baking soda AKA bicarbonate of soda. Some brands may have ingredients that contain gluten. Always be sure to check the label.
- ¼ teaspoon Xanthan Gum You can omit if your flour blend already contains xanthan gum.
- ¼ teaspoon Salt
- 200 grams Butter Melted, I find it easy to melt butter in the microwave.
- 2 large Eggs Room temperature
- 200 ml whole milk
- 60 ml Hot water
How to make the chocolate crumb
- In a large bowl mix together the flour, cocoa powder, and xanthan gum.
- Mix in the sugar, and half the chocolate chips until evenly combined then place in the fridge to chill while you make the filling.
How to make the chocolate cake layer
- Preheat the oven to 180°C/350°F/Gas mark 4.
- Line the baking tin with parchment paper. I recommend having extra parchment paper overlap the sides of the baking tin as this will make the cake easier to remove when cooled.
- In a large bowl mix together flour, sugar, baking powder, baking soda, cocoa powder, xanthan gum, and salt.
- In a separate bowl combine the eggs, milk, melted butter, and hot water. Mix well.
- Add the wet ingredients into the larger bowl that contains the dry ingredient mix and whisk until fully combined and resembles a smooth chocolate cake batter.
- Pour the chocolate cake batter into the prepared baking tin and spread evenly within the tin.
Assembling the chocolate crumb cake.
- With the remaining chocolate chips sprinkle evenly over the top of the chocolate cake batter.
- Remove the crumble mixture from the fridge and spoon the crumble mixture on top of the chocolate cake layer.
- Place in the oven and bake for 40-50 minutes. You can check if it is ready by inserting a wooden skewer and when it comes out clean with only a few crumbs on the skewer it is ready to remove from the oven and leave to cool in the tin for 10 minutes before carefully removing the chocolate crumble cake onto a cooling rack.
- Slice into even-sized squares serve and enjoy.
- Chocolate fudge drizzle - why not go all-in with the ultimate chocolate experience and add a drizzle of hot chocolate fudge sauce and serve with cold ice cream. You can use store-bought fudge sauce or make your own as I have previously used in my Billy miner pie recipe.
Nutritional information is meant as a guideline and is always an approximate calculation. Recipes may include information of various products used. It is your responsibility to check that ingredients you use when making a recipe are gluten free.
I hope you enjoyed this Chocolate Crumb Cake recipe.
Such a perfect cake!! Yummy!
Thank you, Jen, I am so glad you enjoyed the cake.
How much sugar in the crumb mix?
Hi Rhonda, Sorry I seemed to have missed that out in the ingredients. Thank you so much for catching that and letting me know. I have now updated the recipe to include 50 grams of sugar needed for the crumb mix.
Can I omit xantham gum?
Hi Nina, Yes if your flour blend already contains xanthan gum then you don't need to add it to the recipe.