With as many large green salads as I eat, sometimes it can be a struggle to keep them interesting. When I want to add a little excitement I always return to the same basic principles.

Adding more color and a few nontraditional ingredients for extra flavor always does the trick.

I often add plant protein in the form of tofu, beans, or nuts; sour ingredients like olives or mild pickled peppers; and finally something sweet like fresh strawberries, dried cherries or raisins.

To keep your washed, chopped lettuce extra fresh for an extended number of days in the refrigerator, a popular website (http://www.salad-in-a-jar.com/skinny-secrets/salad-in-a-jar) demonstrates how to pack it very tightly into wide-mouth glass jars. Although this site also recommends using a vacuum packing machine, I use no special equipment, and just manually stuff washed lettuce into the jar, filling with as much lettuce as will fit. I swear by this method and use it religiously.

In the January/February 2013 issue of VegNews Magazine, salads-in-a-jar are taken one step further, with a fun way to create a “hearty lunch that’s resolution approved and a joy to eat.”

To build your own beautiful salad in a jar, start by pouring your favorite flavored vinegar or fat-free dressing into the bottom of the jar. Then add your most sturdy ingredients like baby kale, beans, or chopped carrots. Continue to layer with colorful lettuces, other chopped vegetables, and fruits or nuts. Top your salad with the lightest or most delicate ingredients.

Then pop the finished salad into the refrigerator or an insulated bag, and your portable and very healthy lunch is ready to go.

Use any ingredients you wish in the quantities of your choosing. Just be sure to allow enough room at the top of the jar to shake your salad upside down at lunchtime.

With infinite combinations, you can easily have a different, very colorful, crisp, and healthy salad every single day.