Not necessarily a “snack” hack, but I make fake chicken parm sandwich with a toaster oven with microwaveable nuggets, and deli mozzarella slices in toasted potato bread.
If you like sour things, the popcorn + sour patch kids is surprisingly legitimately good! I tried this with buttered puffcorn (not popcorn since I don't like the kernels) and it's like the savory of the butter and the sour/sweet of the sour patch kids are vying for your attention. So good!