Some good ways to soften butter quickly include pounding the butter with a rolling pin or using a warm water bath. Butter can also be softened simply by cutting it into smaller chunks. These smaller pieces tend to soften faster at room temperature.
Place the small chunks of butter near a hot stove to get the full effect. To soften butter by pounding, place the butter in a plastic bag and begin flattening it with a meat pounder or rolling pin. This keeps the current temperature of the butter, while also causing it to soften. To use a warm water bath, put the butter in a bowl on top of a double boiler or sauce pan with hot water.