How to Make Vanilla Ice Cream Without an Ice Cream Maker
To make vanilla ice cream without an ice cream maker, put ice cubes in a plastic bag and hit them gently with a hammer to crush the ice. Then, fill a gallon-sized plastic bag halfway with the crushed ice. Add rock salt, and shake the bag to mix them together. Next, pour milk, sugar, and vanilla extract into a quart-sized plastic bag, squeeze out any excess air, and seal the bag. Put that bag into another sealable plastic bag to prevent spillage. Finally, put the bag with the ice cream mixture into the bag with the ice-salt mixture and shake it for 5-20 minutes.
Use this recipe to have fun making simple ice cream. Ice cream made this way doesn't contain egg yolk, which makes it less rich and creamy than ice cream you may be used to. However, it is quick and easy to make, especially if you have a friend or two to help out. Kids often enjoy making this ice cream, since most of the process involves tossing it back and forth or shaking it. Crush ice. You can purchase pre-crushed ice, or make your own from ice cubes or blocks of ice. Place the ice in a plastic bag and gently, slowly bash the bag with a wooden mallet to break up the ice. Alternatively, use a heavy-duty food processor to break up the ice with brief pulses. Fill a large container halfway full of crushed ice. Use a large container that can be tightly closed, and that won't easily break when shaken around. You can buy an "ice cream ball" for this purpose, which is sturdy and fun to throw around, but you can easily use a gallon-sized zip lock bag or a large plastic jar instead. The container must be large enough to contain the ice cream mixture as well as the ice. Use an even larger container if you are doubling the recipe. Shake rock salt into the ice. Add 6 tablespoons (90 mL) rock salt directly onto the ice, seal the container, and shake until the salt and ice are mixed. It may seem strange, but the rock salt actually cools the ice down! Ice cream will not freeze in a container of regular ice, but salt provides the colder temperature it needs. Rock salt is sometimes sold as "ice cream salt." Ordinary table salt can also be used, but the smaller grains may cool the mixture too rapidly, making your ice cream freeze unevenly. Pour milk, sugar, and vanilla extract into a new zip lock bag. Measure out 1 cup (240 mL) milk, 2 tablespoons (30 mL) sugar, and 1/2 teaspoon (2.5 mL) vanilla extract. Pour all of these ingredients into a quart- or liter-sized zip lock bag. For a richer ice cream, use half-and-half or heavy cream instead of milk. If using an ice cream ball, pour this mixture into the compartment of the ball without ice instead. Skip straight to the "shake" step. Seal the bag after squeezing out the air. Hold the bag upright or have an assistant hold it for you. Press as much air as you can out of the bag, starting just above the level of the ingredients and moving up to the opening. Use the zip lock to seal the bag tightly. The more air there is in the bag, the more likely the bag will be to burst open while you make the ice cream. Seal a second zip lock bag around the ice cream mixture. Open another bag of the same size or larger. Place the bag containing the ice cream mixture inside this additional bag, then seal the same way you did the first. Ice cream needs to be shaken during freezing, and using two bags will prevent it from spilling if one of the bags is broken during the shaking. Put the bag with the ice cream mixture inside the container of ice. Seal the largest container tightly. It should now contain the double-bagged ice cream mixture as well as the loose ice and rock salt slush. Shake the container until the ice cream is ready. Shake the container vigorously, or if the container is sturdy enough and tightly sealed, toss it back and forth. This movement prevents large ice chunks from forming, and stirs a little air into the ice cream as well to make it less dense. The ice cream may take 5–20 minutes to freeze, depending on the temperature, how vigorously you are shaking, and how hard you prefer your ice cream. It may take longer if you are making a larger batch. Wrap the container in towels or wear gloves if it gets too cold to handle. If the ice cream isn't ready after 20 minutes, add more ice and salt, or put in the freezer for no more than 5 minutes. Wipe the bag before opening. Once the ice cream has reached the consistency you enjoy, remove the bag of ice cream from the larger container. Use a dish towel to wipe off the salty water on the outside of the bag, or rinse it briefly under cold water. Now that your ice cream is safe from being mixed with salt, open up the bag and pour it into another container. You can also eat single-serving ice cream made this way straight out of the bag. Use this recipe to make rich, creamy ice cream. If you want a dense, rich vanilla ice cream, you'll need to put in a bit more work than the bag method. This ice cream can also take several hours to freeze, so it's best started earlier in the day if you want it to be ready that night. Separate out 5–8 egg yolks. You'll need at least 5 large egg yolks to create the custard base for the ice cream. Optionally, you can use 6, 7, or 8 to create a richer custard, and therefore a richer ice cream. If you are using small eggs, separate out a single additional yolk. Just go with the amounts listed if you are not sure what size your eggs are. Raw egg whites can be frozen for later use. Whisk together the egg yolks, salt, and sugar. Put the egg yolks in a large bowl, or in an electric mixer bowl. Add 1/4 tsp (1 mL) salt and 1 cup (240 mL) sugar. Whisk until the mixture is pale yellow, contains no lumps or dry spots, and falls off the whisk in thick ribbons when you lift it into the air. You may reduce the amount of sugar to 3/4 cup (180 mL) to make it less sweet, but reducing it further may make the ice cream freeze in larger chunks. Prepare an ice bath. Fill a large bowl halfway with ice or ice water, leaving enough room to place another bowl inside it. You will use this ice bath later to chill the finished custard base, without the risk of freezing it. Optionally, you may keep the 2 cups (480 mL) heavy cream or half-and-half chilled in a small, dry bowl within the ice bath. Otherwise, keep it in the refrigerator. Heat 1 cup (240 mL) evaporated milk to a simmer. Evaporated milk is simply milk that has had a large percentage of its water content removed. This is useful for ice cream to minimize the amount of large ice crystals that form, which allows you to churn less often and less vigorously. If evaporated milk is not available, use whole (full-fat) milk instead. Milk with a lower fat content will likely provide less flavor and may affect the density of the ice cream as well. Add the vanilla. Add 2 tsp (10 mL) vanilla extract to the milk and stir it in. Alternatively, split a vanilla bean pod lengthwise and scrape out the sticky seeds inside into the milk. For the strongest vanilla flavor, the vanilla pod itself can also be placed into the mixture, which is then covered and left to infuse for an hour. Remove the vanilla pod before continuing. There is no need to wait if using vanilla extract. Slowly whisk the hot milk into the egg mixture. Gradually pour the hot milk into the whisked egg in a thin stream, whisking constantly. Be careful not to pour too much milk in at a time, as the heat could turn your excellent ice cream base into sugary scrambled eggs. Heat the mixture again until it thickens. Transfer the newly combined mixture back to the stove and heat at low heat while whisking constantly. Remove it from heat once it reaches a thick, custard consistency. Be careful not to overheat it; remove from heat immediately if you see any lumps of cooked egg or scalded milk skin. Chill the mixture. Transfer the mixture yet again to a container that can fit inside the ice bath without getting filled with water. Place this container into the ice bath and let it chill while you move on to the next step. If you were using the ice bath to keep the cream chilled, remove it before moving the mixture into the bath. In a separate bowl, whisk heavy cream. Whisk 2 cups (480 mL) heavy cream, or substitute half-and-half for a lower fat, but less rich and creamy, recipe. It may take several minutes of whisking by hand, or a shorter time by electric mixer, to create an airy cream that has doubled in volume. Do not beat it so long that it forms whipped cream. Fold the cream into the egg. Once the cream is whisked and the egg-and-milk custard is completely chilled, combine the two together. Using a rubber spatula or other flat implement, fold the cream into the egg mixture. Continue until there are no lumps in the mixture. Freeze in ice cube trays to avoid churning. If you have clean ice cube trays, fill them with the mixture and place them in the freezer. Because more of the ice cream's surface is exposed to the cold surroundings, the ice cream will freeze faster, preventing the formation of large ice crystals. These typically take 4 hours to freeze. To form a more ordinary shape of ice cream, remove the frozen cubes of ice cream from the tray with a spoon and combine in a food processor. Transfer to a larger container and freeze. Alternatively, freeze in a large container and churn frequently. The more traditional method of making ice cream without a machine involves freezing it in one container. However, especially if you are using ordinary milk instead of evaporated milk, large ice crystals will form that ruin the texture of your ice cream and make its flavor uneven. To break up these crystals, you will need to remove it periodically and "churn" vigorously by stirring with an electric mixer or by hand: Churn after about half an hour, before the center has frozen. Churn until the mixture is creamy again. Churn every half hour, breaking up the frozen edges and stirring them into the mixture. Once the ice cream is more evenly frozen (typically after 2–3 hours), leave it until it freezes completely. Finished.  
Use this recipe to have fun making simple ice cream. Crush ice. Fill a large container halfway full of crushed ice. Shake rock salt into the ice. Pour milk, sugar, and vanilla extract into a new zip lock bag. Seal the bag after squeezing out the air. Seal a second zip lock bag around the ice cream mixture. Put the bag with the ice cream mixture inside the container of ice. Shake the container until the ice cream is ready. Wipe the bag before opening. Use this recipe to make rich, creamy ice cream. Separate out 5–8 egg yolks. Whisk together the egg yolks, salt, and sugar. Prepare an ice bath. Heat 1 cup (240 mL) evaporated milk to a simmer. Add the vanilla. Slowly whisk the hot milk into the egg mixture. Heat the mixture again until it thickens. Chill the mixture. In a separate bowl, whisk heavy cream. Fold the cream into the egg. Freeze in ice cube trays to avoid churning. Alternatively, freeze in a large container and churn frequently. Finished. 