There are a couple types of cozies on the market for sale. Some insulate bowls, cooking pots or are made for freezer bag style.
We carry a UL Fabric Cozy on our website. They are handmade Sarah in Washington State. They are flexible, washable and breathable, designed for quart freezer bags and Food Vac bags. They can also be used for items such as Enertia Trail Food and Mary Jane's Organics. They were featured in Backpacker Magazine's "Be An Ultralight Gourmet" December 2007, as part of their UL kitchen setup.
AntiGravityGearcarries quite a number of styles of cozies, both for freezer bags,
Enertia food bags, bowls and for insulating your pots if you cook in
your pan. The cozies they sell are soft sided and UL. The only downside is they are not compact for carrying.
Wilderness Dining carries a light cozy for freezer bags similar to AGG.
You can use a number of items to make a cozy. You can use a
fleece jacket, a hat, or whatever extra clothing you have laying around
(though, if you are a true light packer, you don't have a lot of extra
clothing laying around!, and in bear country, do NOT use your
clothing.)
Eventually you might think, I want something only for my
food. You can do anything from sewing two potholders together, sewing a
fleece pouch, taking a pipe insulator (the ones you use outside on your
hose faucet). These all work great. The main point of a cozy is to
keep the heat in your freezer bag, so that your food doesn't cool too
fast, and it rehydrates properly.
The outside faucet cover is one the
best cozies you can make for winter & cold temperature use. It is
bulky, but it is worth the space taking, you can fit your gear into it
in your backpack, and it holds a quart freezer bag perfectly, and holds
it upright, so you have a "bowl" for eating. This makes for less mess,
and easier eating.
This cozy was made for me by
Marszit. It is about the best I have found - it sits flat, has a shell to
protect the foam inside. Its downside is that it isn't very compact.
For summer time, I like using Fozzil Dishes. They are a line of folding dishes. They are light, affordable and
pretty nifty. The plate and bowls fold up easily and makes a great summer time cozy. The bowl holds a quart freezer bag nicely. If you have small children a stable cozy or bowl will help your child eat with less mess or risk of dropping food on themselves.
Sgt. Rock's DIY Country Time Cozy is an easy to make multipurpose cozy. It can be used as a cozy, eating bowl and mixing bowl. You can use a number of brands from Country Time Lemonade, Kool Aid and Tang to make it. To use as a cozy, put your bag inside the "bowl" and add the water. Seal and do as usual. To eat, roll the bag top over the side. The "bowl" gives you a firm hold. In warmer areas you don't need to do the outside insulation either.