This slow cooker brown sugar rhubarb strawberry slump leans into that cozy, old-fashioned dessert category—somewhere between a cobbler and dumplings—without demanding much from you. The idea is simple: sweet-tart fruit simmers away in the slow cooker while you mix one easy batter with flour, brown sugar, buttermilk, baking powder, and lemon zest. You then dollop that mixture right over the chopped rhubarb and strawberries, clamp on the lid, and let gentle heat do the rest. Slumps (also called grunts in parts of New England) were historically cooked on the stovetop so the biscuit topping steamed instead of baking; the slow cooker mimics that method beautifully, giving you tender, spoonable mounds of dough and syrupy fruit underneath. Because rhubarb and strawberries vary in sweetness and tartness from week to week, this dessert really does “hit different” every time you make it—in the best possible way.
Serve this slump warm, straight from the slow cooker, with a generous spoonful of the fruit and a couple of dumpling-like dollops in each bowl. A scoop of vanilla ice cream is classic, but lightly sweetened whipped cream or vanilla yogurt works just as well if you want something a little lighter. I like to finish each serving with an extra sprinkle of lemon zest or a few fresh strawberry slices for contrast. Coffee or black tea plays nicely with the caramel notes of brown sugar, while a small glass of chilled rosé or a not-too-sweet dessert wine can turn it into an easy, dinner-party-worthy finale.
Slow Cooker Brown Sugar Rhubarb Strawberry Slump
Servings: 6

Ingredients
4 cups chopped fresh rhubarb stalks (about 1 pound, trimmed)
2 cups hulled and sliced fresh strawberries
1/2 cup packed light or dark brown sugar (for the fruit)
1 tablespoon cornstarch
1 teaspoon pure vanilla extract
1 cup all-purpose flour
1/3 cup packed light or dark brown sugar (for the batter)
1 1/2 teaspoons baking powder
1/4 teaspoon fine sea salt
1 teaspoon finely grated lemon zest (from about 1 lemon)
2/3 cup buttermilk, well shaken
3 tablespoons unsalted butter, melted and slightly cooled
Optional: 1 to 2 tablespoons water, if needed to loosen batter slightly
Directions
Lightly coat the insert of a 4- to 6-quart slow cooker with nonstick cooking spray or a thin film of neutral oil. This helps prevent the fruit from sticking and makes cleanup easier.
Prepare the fruit base: Add the chopped rhubarb stalks and sliced strawberries directly to the slow cooker. Sprinkle the 1/2 cup brown sugar (for the fruit) and the cornstarch evenly over the top. Drizzle in the vanilla extract and gently toss everything together with a spatula or your hands until the fruit is evenly coated and the cornstarch disappears. Spread the mixture into an even layer in the bottom of the slow cooker.
Start the slow cooker on HIGH while you mix the topping, just to give the fruit a head start. It will begin to release juices and warm up as you prepare the batter.
Make the “1 mixture” batter: In a medium bowl, whisk together the flour, 1/3 cup brown sugar (for the batter), baking powder, salt, and lemon zest, breaking up any brown sugar clumps with your fingers or the whisk. The lemon zest should be well distributed so every dollop gets a little brightness.
Add the buttermilk and melted butter to the dry ingredients. Stir with a spatula or wooden spoon just until a thick, slightly sticky batter forms. If it seems too stiff to spoon easily, add 1 to 2 tablespoons of water, a splash at a time, until the batter loosels but still holds soft mounds. Do not overmix; a few small lumps are fine.
Dollop the batter over the rhubarb mixture: Lift the slow cooker lid and give the fruit a quick stir so the juices, sugar, and cornstarch are evenly combined. Using a spoon or a small scoop, dollop the batter in 8 to 10 rough mounds over the top of the fruit. You should see patches of fruit peeking through; there is no need to spread the batter into a solid layer. This irregular pattern is what gives the slump its cozy, rustic look and lets the fruit bubble up around the edges.
Cover the slow cooker with the lid, placing a clean kitchen towel underneath the lid if you want to catch excess condensation and keep the topping from getting soggy. Make sure the towel edges are secured up and away from the heating element.
Cook the slump on HIGH for 1 1/2 to 2 1/2 hours, or on LOW for 3 to 4 hours, until the fruit is bubbling and tender and the dollops of batter are set and cooked through in the center. To test, gently press a toothpick or thin knife into the thickest part of a dumpling; it should come out without wet batter clinging to it, though it will be moist from steam.
Once done, turn off the slow cooker and let the slump rest, covered, for 10 to 15 minutes. This brief rest allows the juices to thicken slightly and makes it easier to spoon out clean servings without everything running together.
Serve the slump warm, scooping fruit and dumplings into bowls. Spoon some of the syrupy rhubarb-strawberry juices over the top of each serving. Pair with ice cream, whipped cream, or yogurt if you like, and enjoy the way the tart rhubarb, sweet strawberries, and lemony brown sugar dumplings come together a little differently every time you make it.
Variations & Tips
Because this recipe is built around a single, flexible batter and whatever fruit you have, it invites a lot of variation. For a more intensely tart dessert, increase the rhubarb to 5 cups and reduce the strawberries to 1 cup, bumping the fruit brown sugar up by 2 to 3 tablespoons to balance the acidity. If you prefer a sweeter, more berry-forward slump, swap half or all of the strawberries for raspberries or blueberries; keep in mind that softer berries break down faster, so check for doneness on the earlier side. You can also play with the citrus: use orange zest instead of lemon for a rounder, softer flavor, or add a tablespoon of lemon juice to the fruit layer if your rhubarb is on the mild side. For a warmer, more comforting profile on chilly spring days, stir 1/2 teaspoon ground cinnamon or cardamom into the dry ingredients of the batter, or add a split vanilla bean to the fruit instead of extract. To make it whole-grain, replace up to half of the all-purpose flour with white whole wheat flour; add an extra tablespoon or two of buttermilk if the batter seems too thick. If you need a dairy-free version, use a plant-based butter and a non-dairy “buttermilk” made by stirring 2 teaspoons of lemon juice into 2/3 cup oat or soy milk and letting it sit for 5 to 10 minutes. For a slightly crisper top, transfer cooked dumplings and some fruit to a shallow baking dish and run them under the broiler for 2 to 3 minutes, watching closely. Finally, remember that slow cookers vary: the first time you make this, start checking the dumplings early and note the timing that works best with your particular model so you can reliably recreate your ideal texture in future batches.