We make ice cream in a can all the time at family get togethers. Here's our basic recipe:
Ingredients*
1 cup milk (2% or whole)
1 cup cream
1/2 cup sugar
1/2 tsp. vanilla
3/4 cup rock salt
ice
*For each can
Directions
Combine first four ingredients in a small can (metal baby formula cans work well for this).
Stir together until sugar completely dissolves.
Place lid tightly on can, and place in a larger can (coffee can size works well for this).
Layer in 1/3 cup ice and 1/4 cup rock salt until full (no more than 3/4 cup salt).
Roll around on the ground for 10 to 15 minutes (this can be lots of fun as a team effort). Check ice cream (probably want to stir/scrape sides so it will freeze more evenly).
Roll for another 10 to 15 minutes. You can add mix-ins (fruit, toppings, etc.) when you check the ice cream or just use as a topping when it's done.