For a tangier dessert, stir 1 tablespoon of finely grated lemon zest into the lemon pie filling mixture before pouring it over the cake mix; this brightens the flavor and adds a more “from-scratch” feel. If you prefer a slightly richer, denser texture, swap the whole milk for half-and-half or evaporated milk. To introduce a subtle crunch, sprinkle 1/2 cup of chopped toasted pecans or sliced almonds over the dry cake mix before adding the lemon mixture. A coconut twist is easy: add 1/2 cup of sweetened shredded coconut to the dry cake layer, or sprinkle it on top halfway through cooking so it toasts lightly. For a lighter version, you can use reduced-fat milk and a light lemon pie filling, but the texture will be a bit less lush and more pudding-like. Food safety tips: Always use pasteurized dairy; keep the slow cooker covered while cooking to maintain a safe temperature throughout the dessert. Once the cooking cycle is finished and the cake has rested, refrigerate leftovers within 2 hours to minimize bacterial growth. Reheat portions to steaming-hot (165°F/74°C) before serving again, and discard any leftovers that have been left at room temperature for more than 2 hours. If serving to guests with allergies, note that boxed cake mixes typically contain wheat and may contain or be processed near eggs, soy, and milk; check labels and choose accordingly.