We bake the vast majority of all the bread products we consume here, and especially love to make our own sourdough.  To maintain a healthy sourdough starter, it requires the barm is ‘fed’ regularly with fresh flour, and water, to keep the yeast culture active and lively.  To keep our starter ready to bake with, we generally feed it at least once per week.

Occasionally though we find ourselves with extra barm, and do sometimes find ourselves having to discard the excess.  With an almost 30% increase in flour prices over the last 12 months though, it really pains me to throw any away, so I’m always on the lookout for new recipes to help put the extra barm to good use.

Sourdough gets its lift from active yeast cultures growing in the barm

If you’re maintaining your own sourdough starter you likely already have an arsenal of recipes for various incarnations of sourdough muffins, pancakes, waffles, pizza doughs, and quick breads lurking in your kitchen.

Sourdough blueberry muffins are fine, but we were looking for something a little more exciting

Eager to try something different, I recently stumbled across a recipe for a sourdough chocolate cake. Sourdough, with chocolate?  I was intrigued.  However, some of the reviews seemed to fall a little flat, and honestly, the overall appearance of the cake was a little more plain than I’d like, and not quite something I’d choose to serve to guests.

I was curious to try this cake though, and after reading the criticisms of this recipe, I decided to start by making a few changes.

The first ingredient to go was the vegetable oil.  I’m not a fan of vegetable oil in cakes.  Cakes, in my personal opinion, really deserve pure unadulterated butter.  However, substituting butter for oil isn’t necessarily straightforward, especially when baking, as at room temperature oil is a liquid, and butter is a solid.   The total fat and water contents of oil versus butter aren’t equivalent either.

The recipe also only called for cocoa powder, with no actual chocolate solids, which of course leaves the artery-hardening moisture-enhancing cocoa butter component out completely.  Where’s the fun in that?  My personal philosophy is that if you’re going to indulge, you might as well go the whole hog.  As some of my favorite chocolate recipes utilize both cocoa and chocolate, I hoped that adding a touch of real chocolate, along with substituting the butter, not only might help to balance the ratio of fat in this recipe, but should also contribute to a deeper overall chocolate flavor.  There’s certainly no harm in trying.

This recipe seemed to be missing a key ingredient...CHOCOLATE!

I was a little concerned the cake could be dry with butter, and some suggested the cake was too dense, so I also increased the egg content.

The flat sheet-pan look had to go too.  Hence, a slight makeover with the help of a bundt pan to give the cake a more appealing shape, which of course does require a little more time to bake, but would hopefully make the cake more presentable.

A bundt cake is easy to slice, and a little more interesting to look at than a sheet cake

So, intrigued enough to try turning some of our sourdough barm into some form of this chocolate cake, I began my little experiment in the kitchen, realizing it could go horribly awry.  Fortunately, before I embarked on my quest, Mr. Curbstone gleefully volunteered to consume any evidence of kitchen-borne errors that day.

What emerged from the oven though was a beautiful, aromatic, lush, rich, chocolatey indulgence worthy of any festive occasion, and elegant enough to serve for company.  The texture is moist, but light, definitely not heavy, and the flavor is undeniably chocolate.  So, by request, and just in time for New Year’s Eve, here’s our Double-Chocolate Sourdough Bundt cake.  If you don’t have a sourdough starter, I strongly recommend seeing if you can beg, borrow, or barter a cup from a friend, or neighbor.

Yield: 16 Slices

Bundt Cake:

1 Cup Active Sourdough Starter
1-1/4 cup Whole milk*
2 cups Unbleached All-Purpose Flour
16 Tbsp (8 oz) Butter
4 oz Bittersweet Chocolate (72%)
3 Large Eggs
1-1/2 Cups Granulated Sugar (fine grain Baker’s Sugar preferred)
3/4 cup Unsweetened Baking Cocoa (NOT DUTCH PROCESSED)**
1 Tsp Table Salt
1-1/2 Tsp Baking Soda
1 Tsp Pure Vanilla Extract
1 Tsp Pure Almond Extract

Chocolate Ganache (optional):

6 Tbsp Heavy Cream
2 oz. Bittersweet Chocolate

Preheat Oven to 350F


12-Cup Bundt cake pan

Stand mixer with whisk, and paddle attachments

Prepare the Cake Batter

One to two hours before you plan to make the cake, combine the sourdough starter, milk*, and flour in a large mixing bowl. Mix until the flour is hydrated, and cover with plastic wrap, or a damp kitchen towel.  Allow this mixture to rest at room temperature for 1-2 hours.  The dough should relax, and expand somewhat during this time, but won’t become as bubbly as your starter may appear normally.

Mix the Sourdough starter, milk, and flour, and allow to rest at room temperature for up to 2 hours

Butter, and lightly flour a 12-Cup Bundt cake pan.

When ready to make the cake, melt the butter and chocolate together over medium-low heat, stirring frequently until the chocolate has completely melted.  Set the pan aside to cool for a few minutes.

In the bowl of a mixer, fitted with the whisk attachment, beat the eggs and sugar together until thickened, and pale yellow in color.

Whisk together the eggs and sugar until pale, and thickened

Change to the paddle attachment.  In a small bowl mix together the cocoa, salt, and baking soda, and add to the egg mixture at lowest speed.

Slowly add the cocoa and mix until just combined

On medium speed, add the melted butter and chocolate mixture by slowly pouring it down the inside of the bowl so as not to shock the eggs.  Then mix in the vanilla and almond extracts.

As you add the melted chocolate you'll notice the color of the batter will darken. Mmmm...chocolate

Add one half of the sourdough/milk/flour mixture to the bowl.  Mix on medium speed until evenly incorporated, then add the remaining sourdough mixture, and combine thoroughly.  There should be no remaining streaks of sourdough visible.

Pour the batter into the pan, and level with a spoon or spatula

Pour into a prepared bundt pan, and rap the cake pan on the counter to force out any air bubbles.  Level the top with the back of a spoon or spatula, and bake in the center of the oven for 50-60 minutes, or until a toothpick inserted in the center comes out clean.

The bundt, before ganache...

Allow the cake to cool in the pan for 10-15 minutes before inverting onto a cooling rack, then allow the cake to cool completely.

Prepare the Ganache

To make the ganache, place the chocolate in a heat resistant bowl.

Bittersweet Chocolate

Put the heavy cream in a small saucepan over medium heat, just until the cream begins to boil, and pour the hot cream over the chocolate.

Allow the cream and chocolate to stand for a few minutes before stirring

Allow the chocolate and cream to stand for 3-4 minutes, and then mix with a spatula until thoroughly incorporated.

Then mix together until smooth to form the ganache

Place the ganache in a small zip-top bag, and snip a very tiny piece from the corner, and drizzle the ganache evenly over the shoulders of the cake, letting it run over the sides.  Allow the ganache to set before serving.

Sourdough Double-Chocolate Bundt with Ganache

This cake is moist enough to be served alone, and was excellent with a little sweetened fresh cream.

Slice, and serve

If I’m honest, perhaps the only other thing that may have really put this cake over the top, indulgence-wise, may have been a generous drizzle of a fresh raspberry coulis.  Sadly, we’ve run out of cake, so clearly we’ll have to bake this again during raspberry season.  Oh.  Darn.

Inside, the cake is light, and moist

We have to admit though, as much as we love our sourdough bread, we’ve never seen sourdough look, or taste, quite this good in the Curbstone Valley kitchen.  Enjoy!


* Note, I maintain a relatively firm sourdough barm mixture.  If your barm is somewhat loose, more akin to the texture of a thick pancake-batter, start by only adding one cup of milk. You can add more, up to 1/4 cup of milk, if needed to hydrate the flour.

** Remember, baking is not only art, it’s SCIENCE too!  Dutch Processed cocoa powder, and unsweetened baking cocoa are NOT freely interchangeable in most recipes.  Sourdough barm is acidic (has a low pH), as is the unsweetened cocoa, and they will interact with the alkaline baking soda in this recipe to help give this cake some lift.  Dutch Processed cocoa powder has been treated with alkali, which makes it less acidic (higher in pH) than conventional baking cocoa.  As such Dutch Processed cocoa will raise the pH and NOT react satisfactorily with the baking soda, and alter the texture of the cake.

Not all cocoa is created equal!

To avoid disappointment, only use pure unsweetened baking cocoa in this recipe…the good stuff, of course!