CakesScandinavianEasy

Slow Cooker Sourdough Discard Cardamom Coffee and Walnut Streusel Cake

Name: Slow Cooker Sourdough Discard Cardamom Coffee and Walnut Streusel Cake
Prep time: 15 min
Cook time: 3 h
Total time: 3 h 15 min
Yield: 8 servings
Cuisine: Scandinavian
Ingredients: 1 cup (240 ml) sourdough starter discard, unfed and at room temperature, at room temperature; ½ cup (120 ml) strong brewed coffee, cooled to room temperature; 1½ cups (180 g) all-purpose flour; 1½ teaspoons (7 g) baking powder; ½ teaspoon (2½ g) baking soda; 8 pods green cardamom pods, crushed with the flat of a knife, seeds extracted and ground, pods discarded; ½ teaspoon (3 g) fine sea salt; ⅓ cup (80 g) unsalted butter, melted, melted and cooled slightly; ¾ cup (150 g) granulated sugar; 2 large eggs, at room temperature; 1 teaspoon (5 ml) pure vanilla extract; ½ cup (100 g) packed light brown sugar; ½ cup (60 g) all-purpose flour; 4 tablespoons (57 g) cold unsalted butter, cut into small pieces, cold, cut into 1/4-inch pieces; ¾ cup (90 g) walnuts, coarsely chopped, coarsely chopped; ¼ teaspoon (½ g) ground cardamom

From the MyKitchenBank Kitchen

A tender, subtly tangy spiced cake made with sourdough discard, infused with cardamom and brewed coffee, baked low and slow in a slow cooker. Topped with a crunchy walnut and brown sugar streusel, this Scandinavian-inspired cake is perfect for breakfast or dessert with a cup of coffee.

Prep: 15 min
Cook: 3 hr
Wait: 30 min
Total: 3 hr 45 min
Makes: 1 cake (8 slices)

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Ingredients

8 servings

1 cup (240 ml) sourdough starter discard, unfed and at room temperature, at room temperature
½ cup (120 ml) strong brewed coffee, cooled to room temperature
1½ cups (180 g) all-purpose flour
1½ teaspoons (7 g) baking powder
½ teaspoon (2.5 g) baking soda
8 pods green cardamom pods, crushed with the flat of a knife, seeds extracted and ground, pods discarded
½ teaspoon (3 g) fine sea salt
⅓ cup (80 g) unsalted butter, melted, melted and cooled slightly
¾ cup (150 g) granulated sugar
2 large eggs, at room temperature
1 teaspoon (5 ml) pure vanilla extract
For the streusel
½ cup (100 g) packed light brown sugar
½ cup (60 g) all-purpose flour
4 tablespoons (57 g) cold unsalted butter, cut into small pieces, cold, cut into 1/4-inch pieces
¾ cup (90 g) walnuts, coarsely chopped, coarsely chopped
¼ teaspoon (0.5 g) ground cardamom

Equipment (7)

6-quart slow cooker
Two medium bowls
One small bowl
Whisk or fork
Rubber spatula
Measuring cups and spoons
Instant-read thermometer (optional)

Steps

Before you start

Line a 6-quart slow cooker with parchment paper, leaving an overhang on two sides for easy removal
Brew 1/2 cup strong coffee and let cool slightly
Have all ingredients measured and ready before starting

1
Prepare slow cooker
- Line a 6-quart slow cooker with parchment paper, leaving an overhang on two sides for easy removal after cooking.
- Set the slow cooker to LOW heat.
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Tip: The parchment paper prevents sticking and makes it easy to lift out the finished cake.
2
Crush and grind cardamom
- Using the flat side of a knife, crush the 8 green cardamom pods to release them.
- Remove the black seeds and grind them finely using a mortar and pestle or spice grinder (this should yield about 0.5 teaspoon ground cardamom).
- Discard the pods.
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Ready when: Cardamom seeds are finely ground with no large pieces
Tip: Fresh ground cardamom has much more flavor than pre-ground; grind just before using for best results.
3
Mix dry ingredients for cake
- In a medium bowl, whisk together 1.5 cups (180 g) all-purpose flour, 1.5 teaspoons (7 g) baking powder, 0.5 teaspoon (2.5 g) baking soda, 0.5 teaspoon (3 g) fine sea salt, and the freshly ground cardamom.
- Set aside.
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Ready when: Dry ingredients are evenly combined with no lumps
Tip: Whisk the flour mixture well to distribute the leavening agents evenly.
4
Combine wet ingredients
- In another medium bowl, whisk together 1 cup (240 ml) sourdough discard, 0.5 cup (120 ml) cooled brewed coffee, 0.33 cup (80 g) melted unsalted butter, 0.75 cup (150 g) granulated sugar, 2 large eggs, and 1 teaspoon (5 ml) vanilla extract until well combined and slightly lighter in color.
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Ready when: Mixture is smooth and uniform, sugar is mostly dissolved
Tip: Whisking the wet mixture helps incorporate air and ensures even distribution of ingredients.
5
Make streusel topping
- In a small bowl, combine 0.5 cup (100 g) packed light brown sugar, 0.5 cup (60 g) all-purpose flour, 0.25 teaspoon (0.5 g) ground cardamom, and 0.75 cup (90 g) coarsely chopped walnuts.
- Add 4 tablespoons (57 g) cold unsalted butter pieces and use your fingertips to rub the mixture together until it resembles coarse breadcrumbs with some pea-sized pieces of butter remaining.
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Ready when: Mixture resembles coarse breadcrumbs with visible walnut pieces and some butter chunks
Tip: Keep the butter cold—this ensures a crispy, textured streusel rather than a dense one.
6
Fold dry into wet
- Pour the dry ingredient mixture into the wet ingredients and gently fold together using a rubber spatula until just combined—do not overmix.
- The batter should have some small lumps remaining.
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Ready when: Dry ingredients are just incorporated; a few lumps remain visible
Tip: Overmixing develops gluten and results in a dense, tough cake. Stop as soon as you don't see streaks of dry flour.
7
Pour batter into slow cooker
- Pour the batter into the prepared slow cooker, using a spatula to spread it into an even layer.
- Sprinkle the prepared streusel topping evenly over the batter, covering it completely.
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Ready when: Batter is level and streusel is evenly distributed
Tip: Don't press the streusel into the batter; let it sit lightly on top for maximum crispiness.
8
Slow cook the cake
- Cover the slow cooker with the lid.
- Cook on LOW for 3 hours (180 minutes), or until a toothpick inserted into the center of the cake comes out with a few moist crumbs (not wet batter).
- The edges will pull away slightly from the sides of the slow cooker, and the cake should feel set when gently pressed in the center.
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Ready when: Toothpick inserted into center comes out with a few moist crumbs; edges pull away from sides; center feels set
Tip: Slow cookers vary; check starting at 2 hours 45 minutes. Overcooking will dry out the cake—moist crumbs are ideal.
9
Cool and rest
- Turn off the slow cooker and remove the lid.
- Let the cake rest in the warm slow cooker for 15 minutes to allow it to firm up slightly, then carefully lift it out using the parchment paper overhang.
- Transfer it to a wire rack and let cool for 15 minutes more before slicing.
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Ready when: Cake is cool enough to handle and slice cleanly
Tip: The initial rest in the slow cooker prevents the cake from breaking apart when you lift it out; the parchment overhang makes removal easy.
10
Slice and serve
- Using a serrated knife, cut the cake into 8 equal slices.
- Serve warm or at room temperature with a cup of strong coffee or with a dollop of crème fraîche if desired.
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Ready when: Cake slices cleanly into portions
Tip: A serrated knife cuts through the streusel without crushing it. Warming the knife under hot water between slices keeps them neat.

Good to know

Tips

This cake is best served warm, when the streusel is still crispy and the crumb is tender and moist. If serving later, you can warm individual slices gently to revive the texture.
Sourdough discard adds a subtle tang and moisture without requiring you to feed your starter—it's the ideal way to use discard that would otherwise be composted.
The slow cooker keeps the cake moist throughout cooking, so it's nearly impossible to overbake it compared to a traditional oven. Just check the doneness cue starting at 2 hours 45 minutes.
For a lighter crumb, measure flour by the spoon-and-level method rather than scooping directly from the bag, which can compact the flour and make the cake denser.

Make ahead

You can prepare the dry ingredients and streusel topping up to 24 hours ahead; store separately in airtight containers. Combine the wet ingredients just before cooking for the best rise and flavor.

Storage & reheating

Store the cooled cake, loosely covered with foil or in an airtight container, at room temperature for up to 2 days. Refrigerate for up to 4 days. Freeze whole or in individual slices for up to 3 months in an airtight freezer container. To reheat, warm individual slices in a 300°F (150°C) oven for 10–15 minutes until soft and warm, or microwave on 50% power for 30–45 seconds per slice.

Substitutions

sourdough starter discard, unfed and at room temperature → Buttermilk or Greek yogurt. Use the same quantity. If using yogurt, thin it slightly with milk to match the sourdough discard consistency. The tangy flavor will be less pronounced, but the cake will still be tender.
strong brewed coffee → Hot water or espresso powder dissolved in water. If substituting with espresso powder, mix 1 tablespoon (5 g) espresso powder with 0.5 cup (120 ml) hot water and let cool. Adjust the powder amount to taste if you prefer a stronger or milder coffee flavor.
walnuts, coarsely chopped → Chopped pecans, almonds, or hazelnuts. These offer a similar crunch and richness. Avoid very finely chopped nuts, as they will settle to the bottom; keep them coarse.
green cardamom pods → 1 teaspoon (2 g) ground cardamom (store-bought). Pre-ground cardamom is convenient but loses flavor more quickly; use fresh if possible. Add it directly to the dry ingredients.