In the 1 pound can stir together the cream, milk, beaten egg, sugar, vanilla, and fruit, nuts or chips. Place a little of the ice onto the bottom of the large can and then place the small can into the large can and add the rest of the ice and rock salt (mixing them together somewhat) to fill the empty spaces. Place the lid on the large can. This is the part the kids will love. Roll the can on the floor or patio back and forth for 10 to 15 minutes. Then, open carefully, stir it well and cover and roll again for 5 more minutes. Clean off the salt and water before you open it for great tasting ice cream.