The Downside of Up

• Most recipes assume you'll be baking at or near sea level and can be used without adjustment until you reach altitudes of 3,000 feet or higher. After that, the rarefied air and reduced boiling temperature of water conspire to make your life difficult. The higher you go, the more likely it becomes that your trusted and reliable recipes will fail. Pies and cookies are relatively immune, but breads, cakes and quick breads such as banana bread are prone to over-rising, drying out and sometimes becoming tough and chewy. You can take several steps to counter this.

Don't Get Gassed

• New arrivals in high-altitude settings are often surprised to find how quickly they become fatigued in the thinner mountain air. In much the same way, the leavening in your banana bread can easily overexert itself. Your baking soda or baking powder works by creating small bubbles of carbon dioxide, which expand in the oven's heat and make the banana bread rise. At 6,000 feet it rises too vigorously. The gas escapes from your batter, leaving behind a dense, underinflated or fallen banana bread. Cut back your baking powder by 1/4 to 1/2 teaspoon, or your baking soda by 1/8 teaspoon.

Moisturize, Moisturize, Moisturize

• The arid, parched air at high altitudes can make your skin feel tissue-paper dry unless you keep it moisturized, and your banana bread needs just as much help. Increase the wet ingredients in your recipe by up to 1/4 cup, as needed, to keep it moist and counteract the drying effect of the high altitude. Acidic liquids such as buttermilk and sour cream are especially helpful, because acidity counters some of the effects of high-altitude baking. They also enrich your batter and add a pleasant flavor. If your bananas are falling-apart brown and mushy, they'll add acidity and moisture as well as a more assertive banana flavor.

Try a Little Tenderness

• Banana bread or muffins baked at 6,000 feet can also require some adjustment in the dry ingredients, to help counter a tendency to toughness. For example, sugar tends to make quick breads chewier and tougher. Cut it back by reducing each cup of sugar by up to 2 tablespoons, as needed. You might also need to cut back on your fat by a comparable amount, and add an extra tablespoon or two of flour to each cup. The combined effect of these changes will be a tender banana bread that's more like what you made at sea level.

Take Your Time, Do It Right

• A few other adjustments have less to do with the ingredients and more to do with method. Remember your banana bread will rise more than usual, so don't over-beat the eggs and don't cream your butter and sugar as long as you did at sea level. Fill your pans half-full rather than two-thirds full, because the banana bread will rise more. At elevations below 6,000 feet, most bakers turn up the heat in their ovens, but at 6,000 feet or higher it's best to extend your baking time by a few minutes instead.