My grandfather showed me this 3 ingredient dessert and it instantly takes you back in time.

To lean even harder into the root beer float nostalgia, you can sprinkle the top of the glazed cake with a handful of crushed root beer barrel candies just before serving for extra flavor and crunch. If you prefer a deeper, almost caramelized flavor, use a spice cake mix instead of yellow; the warm spices play nicely with the root beer’s sassafras notes. For a slightly lighter version, you can use reduced-fat vanilla ice cream or frozen yogurt, though the glaze will be a bit thinner. If you don’t have yellow cake mix, white cake mix works as a neutral base, while chocolate cake mix gives you a flavor reminiscent of a root beer chocolate float.

For individual portions, you can grease heatproof ramekins, divide the batter among them, and nestle them in the slow cooker with a bit of water at the bottom; cooking time will be shorter, so start checking around 1 1/2 hours on HIGH.

Food safety tips: Always use regular (not diet) root beer, as some artificial sweeteners can break down oddly with heat. Keep the ice cream frozen until about 10 to 15 minutes before you need it so it doesn’t sit in the temperature “danger zone” (40°F–140°F) for long; once softened and mixed with root beer, use it immediately. Refrigerate any leftover cake within 2 hours of serving, storing it covered in the slow cooker insert or an airtight container, and consume within 3 days. Reheat leftovers gently in the microwave until just warm, avoiding overheating, which can dry out the cake and cause the glaze to separate.