This slow cooker 4-ingredient banana split cake is one of those retro dessert tricks my grandma used to pull out on hot summer nights when she didn’t want to turn on the oven. It’s basically a warm, gooey mash-up of strawberry cake and soft baked bananas, and it tastes like the inside of a banana split without the fuss. Everything bakes together in the slow cooker into a bubbly, spoonable dessert that people literally scrape the crock for. With only four pantry-friendly ingredients and almost no prep, it’s perfect for busy weeknights, cookouts, or anytime you need a nostalgic crowd-pleaser with minimal effort.
Serve this slow cooker banana split cake warm, scooped straight from the crock onto small dessert plates or into bowls so all the pink cake, bananas, and juices stay together. Top it with a scoop of vanilla ice cream or a dollop of whipped cream so it melts into the warm, gooey cake. You can add a drizzle of chocolate syrup and a few chopped nuts if you want to lean into the banana split vibe. It pairs really well with iced coffee, cold brew, or a simple glass of milk, and it’s easy to bring outside for backyard dinners or game nights since it stays warm on the “warm” setting of your slow cooker.
Slow Cooker 4-Ingredient Banana Split Cake
Servings: 8

Ingredients
4 large ripe bananas, peeled and sliced into 1/2-inch rounds
1 (15.25-ounce) box strawberry cake mix (dry mix only)
1/2 cup (1 stick) unsalted butter, melted
1 (20-ounce) can crushed pineapple in juice, undrained
Directions
Lightly grease the inside of a 4- to 6-quart slow cooker with nonstick spray or a thin layer of butter to help prevent sticking and make cleanup easier.
Layer the banana slices evenly over the bottom of the slow cooker, covering as much surface area as you can. It’s okay if some slices overlap; this will become the soft, fruity base of the dessert.
Pour the entire can of crushed pineapple with all of its juice evenly over the bananas. Use a spatula or spoon to gently spread the pineapple so it covers the bananas in a fairly even layer.
Sprinkle the dry strawberry cake mix evenly over the pineapple layer. Do not stir. Try to cover the fruit completely with the dry mix, breaking up any big clumps with your fingers or a spoon.
Slowly drizzle the melted butter evenly over the top of the dry cake mix, aiming to moisten as much of the surface as possible. Some dry spots are okay; the fruit juices will bubble up and help hydrate the mix as it cooks.
Cover the slow cooker with the lid and cook on HIGH for 2 to 2 1/2 hours, or on LOW for 4 to 4 1/2 hours, until the top looks mostly set, the edges are bubbly, and a spoon inserted into the center hits soft, gooey cake rather than dry powder. Avoid lifting the lid during the first 90 minutes so the heat stays consistent.
Once cooked, turn the slow cooker to WARM and let the dessert sit for 10 to 15 minutes. This helps the juices thicken slightly while still keeping everything warm and spoonable.
To serve, scoop the warm banana split cake into shallow bowls or onto plates, making sure to dig all the way down to get bananas, pineapple, and strawberry cake in each serving. Enjoy as-is or top with vanilla ice cream, whipped cream, and your favorite banana split-style toppings.
Variations & Tips
To lean even more into the banana split theme, add a handful of chocolate chips and chopped walnuts or pecans on top of the dry cake mix before drizzling on the butter. For a slightly less sweet version, use a light or sugar-free strawberry cake mix and canned pineapple in 100% juice instead of syrup. You can also swap the crushed pineapple for pineapple tidbits if you prefer more distinct fruit pieces, or replace half the pineapple with sliced fresh strawberries for extra berry flavor (just don’t reduce the total liquid too much or the cake may be dry). If you only have salted butter, you can use it and simply skip adding any extra salt. For a smaller household, you can halve the recipe and cook it in a 2- to 3-quart slow cooker, checking for doneness a bit earlier. Food safety tips: Always make sure your slow cooker starts with a hot setting (HIGH or LOW as directed) and keep the lid on so the temperature stays safe while cooking. Leftovers should be cooled, then transferred to an airtight container and refrigerated within 2 hours; reheat portions in the microwave until steaming hot. Discard any dessert that has sat at room temperature for more than 2 hours, especially in warm weather. If you’re serving this at a summer gathering, keep the slow cooker on the WARM setting and only scoop out what you need at a time so it stays at a safe temperature.