This slow cooker 5-ingredient boiled raisin cake is pure Midwest nostalgia with almost no effort. You literally drop shriveled hard raisins into cold tap water, pair them with just three pantry ingredients plus a bit of baking powder, and let the slow cooker do its thing. It’s inspired by old-fashioned boiled raisin cakes that our grandmas used to make on the stovetop, but this version is hands-off and weeknight-friendly. The result is a moist, gently spiced cake that somehow disappears faster than anything else on the dessert table.
Serve this warm straight from the slow cooker, scooped into bowls like a cozy pudding cake. I love it with a scoop of vanilla ice cream or a dollop of whipped cream so it melts into all the raisin-y nooks and crannies. For a simple afternoon snack, let it cool and slice it into squares to go with coffee or hot tea. It also makes a great bring-along dessert for potlucks—just keep it in the slow cooker on warm and let people help themselves.
Slow Cooker Boiled Raisin Cake
Servings: 8
Ingredients
2 cups shriveled hard raisins
2 cups cold tap water
1 cup granulated sugar
1/2 cup neutral oil (such as canola or vegetable)
2 cups self-rising flour
Directions
Lightly grease the inside of a 4- to 6-quart slow cooker with a little oil or nonstick spray to help the cake release and make cleanup easier.
Place the slow cooker crock on a flat surface, such as your kitchen counter. Pour in 2 cups of cold tap water.
With clean, dry hands, drop the shriveled hard raisins into the cold tap water in the slow cooker. The water should fully cover the raisins; they will look a little sparse at first but will plump as they cook.
Stir in the granulated sugar directly into the water and raisin mixture until it’s mostly dissolved. It doesn’t need to be perfect—just give it a good stir so the sugar starts to blend into the liquid.
Drizzle in the neutral oil and stir again to combine. At this point you’ll have a sweet raisin-studded liquid base sitting right in the slow cooker.
Sprinkle the self-rising flour evenly over the top of the liquid mixture in the slow cooker. Using a sturdy spoon or spatula, gently fold the flour into the wet ingredients until no dry streaks remain. The batter will be thick and lumpy from the raisins—that’s exactly what you want.
Smooth the top of the batter a bit with the back of your spoon so it cooks evenly. Avoid pressing too hard; just level it out.
Cover the slow cooker with its lid. Cook on HIGH for 2 to 2 1/2 hours, or on LOW for 4 to 4 1/2 hours, until the cake is set in the center and a toothpick or thin knife inserted into the middle comes out with a few moist crumbs but no wet batter.
Once cooked, turn off the slow cooker and let the cake sit, covered, for 10 to 15 minutes. This resting time helps it firm up slightly while staying moist and tender.
Serve the cake warm, scooping it directly from the slow cooker into bowls. Store any leftovers, fully cooled, in an airtight container in the refrigerator for up to 4 days. Reheat individual portions in the microwave until just warm.
Variations & Tips
Use golden raisins or a mix of raisins for a slightly different flavor and color. For a cozy spice twist that still keeps things simple, add 1 teaspoon ground cinnamon and 1/4 teaspoon ground nutmeg or allspice to the batter when you mix in the flour. If you don’t have self-rising flour, you can make your own by whisking together 2 cups all-purpose flour, 3 teaspoons baking powder, and 1/2 teaspoon fine salt before adding it to the slow cooker. To make this dairy-free, just confirm your self-rising flour doesn’t contain milk powder and serve with a non-dairy ice cream or whipped topping. For a slightly lighter cake, you can replace half of the oil (1/4 cup) with unsweetened applesauce; the texture will be a bit softer but still delicious. FOOD SAFETY TIPS: Always start with clean hands when dropping the raisins into the water and mixing the batter. Make sure your slow cooker is in good working condition and that the crock is not cracked. Cook the cake fully; it should reach at least 190–200°F in the center if you check with an instant-read thermometer. Cool leftovers promptly and refrigerate within 2 hours of cooking. Reheat leftovers thoroughly until steaming before serving, and discard if they develop an off smell, unusual color, or mold.