Stir butter with a wooden spoon in a medium bowl until creamy. Add lime juice, zest and chili-garlic sauce, and stir until evenly mixed. Scrape onto a piece of waxed paper. Fold one edge of the paper over butter and smooth, shaping the mixture into a log about 5-in. long. Roll the log and seal by twisting the ends.
Chill log in the refrigerator for at least an hour before using. Wrap in foil and refrigerate up to 1 week or freeze up to 3 months.