More and more of us take along some type of thermos filled with coffee, soup, or some other homemade delight. Cleaning a thermos can be tricky because it’s hard to get into with a sponge or scrubber. Most aren’t dishwasher safe either. To rid the residue add 1/4 cup of baking soda to 1/2 quart of water to your vessel. Seal and shake. Empty, rinse, and wipe clean. The mildly abrasive baking soda will have loosened any buildup. Now you can fill’er up again.