Grandma pat always served this straight from the pan with a spoon and a smile—nobody waited for plates.

Variations & Tips
For a slightly less sweet version, choose pineapple canned in juice rather than heavy syrup and keep the optional chocolate and nuts on the lighter side. You can also cut the butter back to 6 tablespoons; the top will be a bit less rich but still crisp and golden. If you prefer a more pronounced banana flavor, add an extra banana or two, but keep in mind that very overripe bananas will soften considerably and blend into the fruit layer. To lean even harder into the banana split idea, sprinkle mini chocolate chips and a few extra chopped nuts over the cake in the last 5 to 10 minutes of baking so they warm through without burning. A few maraschino cherries on top just before serving give a nostalgic soda-fountain look. You can also swap in a strawberry pie filling for half of the cherry pie filling for a cherry-strawberry mix. For dietary adjustments, a gluten-free yellow cake mix works well; just follow the same directions, keeping an eye on the baking time, as some gluten-free mixes brown faster. Dairy-free margarine or a plant-based butter substitute can stand in for the butter, though the flavor will be slightly different. Always check labels on cake mixes and toppings for allergens such as wheat, dairy, soy, or nuts. Food safety tips: Because this dessert contains fresh bananas and a very moist fruit layer, avoid leaving it out at room temperature for more than 2 hours. Once it has cooled to just warm, cover the pan and refrigerate leftovers. Reheat portions gently in the microwave or a low oven until warmed through. If you serve this directly from the hot pan, remind guests not to touch the sides or handles, as ceramic and glass baking dishes hold heat for a long time. Use oven mitts and set the dish on a heatproof surface. Discard any leftovers that have been left unrefrigerated for more than a couple of hours, especially in warm weather.