Affordable and versatile, lentils take more than half an hour to cook. So when you come home tired and hungry at the end of a long day, lentils may not be the first thing you think of making for dinner. If you cook lentils in advance and freeze them, you can quickly reheat them and use them in meals you can put on the table in a jiffy. Choose one or more of the firmer varieties of lentils, such as green lentils -- also known as French lentils -- black beluga lentils or the more common brown variety, to freeze. Orange, red and yellow lentils are smaller and more delicate, so they tend to become mushy when frozen, thawed and reheated.
Strain the lentils well after cooking.
Put the strained lentils into plastic or glass food storage containers of the appropriate size. If you're using plastic food storage bags, press out excess air before sealing them. If you're using glass storage containers, leave 1 inch of space at the top of the container to allow for expansion during freezing.
Label the containers. Include the date on the label. Use frozen lentils within six months of freezing.