Coming home after a long day and scraping together a meal for the family is a challenge that almost every parent faces on a regular basis. Prepared foods are a convenient stopgap, but canned, frozen or microwaved meals aren't very inspiring as a steady diet. Slow cookers provide a better alternative, quietly simmering hot homemade meals all day while you're out. For example, a beef stew can spend up to 10 hours in your cooker, when prepared correctly.

Frugal home cooks have known for centuries that slow cooking could turn even the toughest, most indigestible meats or vegetables into savory and comforting foods. When an open fire was the primary cooking method, slow cooking took place in a heavy metal or earthenware pot nestled into the coals at the edge of the fire. Slow cookers recreate that gentle heat with a stoneware crock and a small electric element, safe enough to leave unattended through the day.

Slow cookers invariably offer a high and a low setting, with more sophisticated models adding timers, automatic or programmable temperature control, or a keep-warm setting. Most dishes will cook in 2 to 4 hours at the high setting, or in 6 to 8 hours at the low setting. Beef stew can cook for 10 hours on the low setting of most slow cookers without its quality suffering. If your plans for the day require that long a cooking time, you'll need to make a few adjustments to the recipe.

The most important ingredient in your stew is the beef, so choose it wisely. For long cooking, your best bets are tough cuts such as chuck and shank, which have enough marbling and connective tissue to stay moist. Avoid lean cuts such as the round, which will dry out or disintegrate after a few hours. Cut the beef into larger pieces, up to 2 inches, rather than spoon-sized 1-inch cubes. "Waxy" potatoes such as Yukon Gold will hold their shape better than russets, and skin-on baby potatoes are even better. Cut vegetables such as carrots or parsnips slightly larger than you normally would, so they'll retain their texture for longer.

Prepare the stew according to your favorite recipe, and fill the stoneware crock. Turn the cooker to its "Low" setting, and let it do its work. Don't lift the lid to check on your stew, if you happen to come home during the day. Letting out the accumulated heat can easily extend your cooking time an hour or more. When you get home at the end of the day, ladle out a cup or two of the cooking juices and whisk in a slurry of cold water and instant-mix flour. Return the mixture to your cooker for 15 to 20 minutes while you set the table, so the stew can thicken. Taste it and adjust the seasoning if necessary, then serve.