I’ve been cooking at altitude (4500 ft above sea level and above) for my whole life with a couple of brief exceptions, and it’s a lot simpler than cookbooks make it seem if you understand two basic principles:
- Almost everything is going to take longer to cook/bake: this is because water boils at a lower temperature at altitude, and cooking is basically using heat to drive water out of things so you can change their chemical structure into something more nourishing or delicious (a process called pyrolysis; it’s responsible for caramelization, turning starches into sugars, breaking down collagen in muscle tissue, etc.). I get around this problem most of the time simply by raising my oven temp by 15°F for baked goods (below 400°; above, it doesn’t seem to matter) or by adding 1/3x-1/2x more time to recipes—this is especially necessary for slow-cooked meat and beans (but see below for beans as well). I can’t tell you how many times I’ve followed the recipe for a big chunk of meat that was supposed to be done at time X and ended up serving dinner at X + 1 hour.
- You need to add water to everything: This is because the higher you go in our atmosphere, the less water it can hold. As a result, higher elevations are often more desert-y, which makes the dehydration of foodstuffs even worse. I know this advice seems to run counter to what I just said about needing to drive water out of things (except for in candy-making; see below). But it makes sense once you realize that water is also the main way cooking heat gets conducted into and through the thing you’re trying to cook. So, you want to start out with enough, even if you eventually want it gone, or it’s gonna burn where it touches your heat source and be raw otherwise. I add at least 1-2 T of water to everything I cook at altitude, and that includes sautéed onions/garlic (ever wondered why those onions burnt *way* before the prescribed “5 minutes” in the recipe? Now you know!) For slow-cooking soups and braises, you’re going to want to check it and probably add more liquid every 30 minutes. Note that dryness has a *major* effect on legumes: if those dried pintos have been sitting in your cupboard for 6 months, you’re going to have to rehydrate their starches before you can pyrolyze them. I add at least 1/4C extra water to all my beans and rice (even if you’re pressure-cooking!), and I expect to cook them at least 1/3x longer than suggested. For baked goods, I often just back off on the flour in recipes by 2T to 1/4 C to achieve the same result as adding more liquid.
After all my bragging about simplifying things, I do have to point out three exceptions to the above principles for serious cooks:
- Candy-making: b/c there is less water in your sugar than at sea level, and it’s going to boil off at a lower temperature, you will get to all of your ball/crack temperatures *much* faster than recipes tell you, and to get the right effect, you’ll want to reduce these benchmarks proportionally according to the temperature that water boils at your elevation. The general rule is that boiling temp goes down 1°F for every 500 ft above sea level. I live at 4500 ft right now, so I lower all my benchmarks 9°F : e.g., soft ball (for fudge) starts happening at 225° for me, not 234° as advertised. Ruined *so* much fudge and caramel before I figured this out….
- Leavening: There is less air pressure, so everything is going to rise faster for you. Sometimes, I back off slightly on the yeast or baking powder to adjust for this (I don’t measure, just scoop a little under, and it seems to work), and sometimes I just plan to be putting the risen bread in the oven earlier than the recipe says. Also, I’m terrible at making bread, so you’ll probably just want to do your own thing here.
- Meringues: On the air-pressure note, there are certain kinds of meringue recipes that just aren’t going to work perfectly for you at altitude, so don’t beat yourself up (har har) for weeping meringue toppings, fallen soufflés, and macarons with hollow shells. See this post on soufflé pancakes for more detail.
The Rookery 