A batch of oatmeal-raisin cookies I baked came out flat. I used the same ingredients I had before, but I left the butter on the counter for a long time, and it got soft in the heat. Was that the problem?

A batch of oatmeal-raisin cookies I baked came out flat. I used the same ingredients I had before, but I left the butter on the counter for a long time, and it got soft in the heat. Was that the problem?

— Jessica D., via email

Oversoftening the butter was very likely the problem. In addition to its other attributes, such as flavor and texture, butter contributes body to doughs.

Butter below 67 degrees stays solid, and in that state is better at trapping air, which you need for better baked goods. Butter warmer than that — room temperature — came into vogue in the 1950s because it can be easily whipped by hand mixers.

Before that, kitchens had heavy stand mixers, which could handle colder, more solid butter. But puny, little hand mixers would burn up under the stress, so we were told the butter had to be soft.

If butter's too warm, however, it won't hold as much air, and your cookies are flat. So don't oversoften it.

When a recipe calls for softened or room-temperature butter, soften it only until you can press it lightly with a finger and leave a dent, not until you can stick your finger all the way through it.

The microwave isn't a good shortcut for softening butter. Because it heats food from the center outward, the middle of the stick might get liquid before the outside even looks soft.

Instead, try cutting butter into small cubes and letting it sit at room temperature for about 10 minutes. Smaller cubes soften more quickly.

Or use the old trick of whacking the butter several times with a rolling pin or meat mallet, just until it's pliable. That softens it without oversoftening — and it's a great way to take out your aggressions.