Sunday Sweetness: Just 4 ingredients. I make it when I want dessert handled hours ahead.

This 4-ingredient slow cooker toasted fluff cake is my kind of Sunday sweetness: you stir it together in minutes, walk away, and a few hours later dessert is already handled. It bakes up right in the slow cooker with a dark, toasty caramelized top and long, sticky webs of glossy melted marshmallow fluff that make everyone at the table ooh and ahh. The idea is a simple Midwestern-style dump cake twist—using boxed cake mix and jarred fluff—so busy home cooks can get that cozy, from-scratch feeling without hovering over the oven.

Serve this warm right out of the slow cooker, scooped like a cobbler so you get both the gooey center and the toasted caramelized crust. A scoop of vanilla ice cream or a dollop of whipped cream melts into the glossy fluff and makes it extra special. For a simple family night, I just pass around small bowls and spoons, but if friends are over, I set out toppings like mini chocolate chips, sliced strawberries, or crushed graham crackers so everyone can dress up their own serving.

Servings: 8

1 box (15.25 ounces) yellow cake mix

Lightly grease the inside of a 5- to 6-quart slow cooker with butter or nonstick spray to keep the cake from sticking and to help the edges caramelize nicely.

In a medium mixing bowl, whisk together the dry yellow cake mix and the whole milk until just combined and mostly smooth. A few small lumps are fine; you do not want to overmix.

Whisk the melted butter into the batter until fully incorporated. The batter will be thick but pourable.

Pour the batter into the prepared slow cooker, smoothing the top into an even layer with a spatula so it cooks uniformly.

Spoon the marshmallow fluff in big dollops all over the surface of the batter. Do not stir it in; you want pockets and streaks so it can melt into glossy, sticky ribbons and toast on top as it cooks.

Place a clean kitchen towel over the slow cooker crock, then set the lid on top of the towel. This helps catch condensation so the top of the cake can develop that dark, toasted, caramelized crust instead of getting soggy.

Cook on HIGH for 2 to 2 1/2 hours, or on LOW for 4 to 4 1/2 hours, until the edges are deeply golden brown and toasted and the center is set but still a little gooey from the melted fluff. The marshmallow on top should look glossy and slightly caramelized, with sticky strands stretching if you pull it with a spoon.

Once done, turn off the slow cooker and let the cake sit, uncovered, for 10 to 15 minutes. This short rest helps the caramelized top set up just enough while staying shiny and stretchy.

To serve, scoop the warm cake straight from the slow cooker, making sure each serving includes some of the dark toasted edges and the glossy melted fluff from the top. Enjoy as-is or with ice cream or whipped cream.

For chocolate lovers, swap the yellow cake mix for a chocolate cake mix; the contrast between the dark cake and the shiny white fluff is beautiful and tastes like a gooey s’mores brownie. If your family prefers things less sweet, use a butter or white cake mix and add a pinch of salt to the batter to balance the marshmallow. For kids who love s’mores, sprinkle 1/2 cup crushed graham crackers over the batter before adding the fluff so they toast into the crust. You can also swirl the fluff slightly into the top inch of batter with a butter knife for more marbled ribbons instead of big pockets. If you need to make it dairy-free, use a dairy-free cake mix (or check the box ingredients), swap the milk for oat or almond milk, and use a plant-based butter; the texture will still be tender and gooey. For a smaller household, you can halve the recipe in a 3-quart slow cooker and start checking for doneness about 30 minutes earlier. Leftovers keep well covered in the fridge for up to 3 days; rewarm individual scoops in the microwave for 15–20 seconds to bring back the glossy, stretchy marshmallow top.