But how to have pre-cut lettuce without having it get gross before you get around to using it? Between my sister and I, we came up with a nearly perfect way to have your lettuce waiting on your beck and call. I say "nearly perfect" because, while lettuce stored this way will stay good for 5 or 6 days, it does eventually get gross--nothing lasts forever.
First, wash and spin dry your lettuce. I love red leaf and use it almost exclusively. If your lettuce is a little bit limp, soak it in cold water (add ice cubes if necessary) after cutting it to help it re-hydrate. To dry lettuce, I like a salad spinner over paper towels because it removes most of the surface water, and moisture is a death sentence to lettuce while in storage.
Put the washed and dried lettuce in a gallon sized (or other appropriately-sized) zip-top bag (don't pack it too tight), and tuck a paper towel on each "side". The paper towels will absorb any left-over moisture. After using some of the lettuce, change out the paper towels if they're at all damp.
Finally, squeeze out most of the air and seal the bag. I also use a permanent marker to label the bag. Maybe it's just me, but I need to be reminded what's in my paper towel-lined bags.
If you ask my kids they'll said I don't promise anything (except I'll promise I love them, that's easy to follow through with). So I'll almost-promise that you'll have less lettuce go bad in your fridge if you store it this way because you'll be much more likely to use it up fast. More salad is good for everyone, and you're bound to eat more of it when the lettuce is ready and waiting for you.