Having a hot cuppa on a cold day in the mountains is a wonderful thing. But most vacuum bottles (technically, Thermos is a trademark, like Levis) just don’t cut the mustard. The solution is to get a serious, screw-top vacuum bottle that’s built to take some abuse. True, you’ll pay a weight penalty, but the trade-off is a reliable container. I have a fully functional 20-year-old, Thermos-brand steel vacuum bottle that I don’t believe I’ll ever replace it (I took it up Denali several years back). As for Everest climbers, they don’t use anything more exotic than that.
REI sells a very nice stainless-steel vacuum bottle in both one- and half-liter sizes, complete with a tough plastic threaded cap and insulated cup. The liter model goes for $28, the half-liter for $24 (www.rei.com). L.L. Bean sells similar-sized bottles for $19 and $22, respectively, plus a big 48-ounce model for $29 (www.llbean.com).
Mix all these ingredients in a saucepan and heat until blended. Pack along a little whipped cream, too, for topping it off! Better yet, add a few ounces of good bourbon before serving.