Baking at High Altitude can be very frustrating, especially if you are used to baking at sea level! A lot of recipes are written for sea level and it is important to understand the adjustments that need to be made in order for recipes to come out properly. Typically you think of High Altitude baking as anything over 5,000ft above sea level, but did you know that you can start seeing effects around 3,000ft? And anything over 5,000ft is not the same, as you increase in elevation you need to keep making adjustments. I will go over some general adjustments, however adjustments can vary depending on which recipe you are using. It is always an experiment when modifying recipes for high altitude!
Baking Powder & Baking Soda:
One of the most important things is to adjust your baking powder and baking soda in your recipes. Baked goods rise faster at altitude, so too much leavening can lead to baked goods with fallen centers. Also, baking soda is more powerful than baking powder. Once you are over about 8,500ft you might want to consider switching to just baking powder. A rough guide is below:
3,000ft: 3/4 of original amount
5,000ft: 2/3 of original amount
7,500ft: 1/2 of original amount
Once you get to about 10,000ft you might want to consider decreasing it even more.
You want the mixture to set quicker so you need to add in some extra flour. This will make the mixture thicker and bake quicker. Once you are above 5,000ft add an extra tbsp for every cup of flour in the recipe.
Too much sugar can be detrimental to the structure of your baked goods. Above 3,000ft decrease by 1 1/2tsp for every cup in the recipe. Once you are over 5,000ft, decrease by 1 tbsp for every cup of sugar in the recipe.
Since baked goods rise faster at high altitude, you want to set the oven temperature higher so it will set quicker. I have found that oven temperature does not change drastically with the various altitudes, I typically raise the oven temperature 10 degrees once you are over 5,000ft. If you feel that you want things to cook faster then you can raise it as much as 25 degrees above the sea level temperature, but I would not go any higher than that.
At high altitude you want your mixture to be thicker so it can cook quicker. Because of this you want to switch to buttermilk once you are over 3,000ft. And once you are over 5,000ft you want to add 2tbsp, and add and additional 2 more tbsp for every 2,000ft after that. Example, if you are at 7,000ft you want to add 2tbsp + 2tbsp, for a total of 4 tbsp, which is 1/4cup.
Once you are over 5,000ft it can be helpful to add an extra egg to help add some moisture so your baked goods aren’t dry. Eggs also help with the structure and texture.
Salt is obviously used for flavor, but can also help stabilize the structure of your baked goods. Once you are over 5,000ft, you can increase the salt by 1/4-1/2 tsp. This step is optional.
As you can see there are a lot of adjustments that can be made when baking at high altitude. This can be helpful when modifying your favorite recipes. However, sometimes it is nice to find high altitude recipes where someone has gone through the trial and error and made the adjustments already! Hopefully this information has been helpful, and search around my site for recipes that are already optimized for high altitude!
For some more advice from baking experts, check out this article from Sizzle & Sear! Mountainside Bakery and other experts answer questions that you might have about baking.