In a medium bowl, combine the softened unsalted butter, minced garlic, chopped fresh parsley, chives, and rosemary. Add the salt and freshly ground black pepper.

Mix all the ingredients together thoroughly using a fork or spatula until everything is well incorporated and the butter has a uniform color. Ensure no streaks of butter or herbs remain separate.

Transfer the garlic herb butter mixture onto a piece of parchment paper or plastic wrap. Shape it into a log, about 5cm (2 inches) in diameter, by rolling and pressing the paper around it.

Twist the ends of the parchment paper or plastic wrap tightly to secure the log. Refrigerate the butter for at least 30 minutes (or until firm) before slicing and using.