Many cake and cookie recipes call for softened butter, and you want it to be soft enough to incorporate the maximum amount of air needed for a light and tender product. Butter will usually soften at room temperature in about 30 minutes, but this will vary depending on the warmth in your kitchen.
Before beginning your recipe, test to see if the butter is soft enough by gently pressing the top of the stick with your index finger. If an indentation remains and the stick of butter still holds its shape, it’s perfectly softened. If you can’t make an indentation, the butter is still too firm. If your make an indentation and the stick of butter doesn’t hold its shape, it’s too soft.