According to the USDA, a single serving of butter is about 1 tablespoon, making this an appropriate size for an individual pat. Packaged individual butter pats, such as Land O’Lakes Continentals, are typically just over 1/2 ounce.
An easy method for making individual pats of butter as a home cook is to slice a stick of butter along the tablespoon marker lines typically found on the waxed paper wrapping. Decorative butter pats can be made with any small mold pan. Candy molds are typically well suited for this purpose. Look for mold cavities that hold between 1/2 ounce and 1 ounce of liquid.