This is a great idea for camping or road trip!
Before leaving, divide one small box of instant chocolate pudding (or whatever flavor you like) among 4 zip-type bags. Add 1/4 cup powdered milk to each bag. Make sure the bags are tightly sealed.
When you are ready for a pudding snack, add 1/2 cup water to each bag. Seal the bag and shake, roll and squish the bag for a few minutes. Hold the bag in an icy cold stream or toss into an ice chest for a few minutes until the pudding sets. Open the bag and enjoy pudding with a spoon or snip off one corner of the bag and squeeze the pudding right into your mouth!