Bring shredded cheese to room temperature in a medium mixing bowl (allow 30 minutes). Add sour cream and pecans. Beat with an electric mixer until combined and mixture is creamy. Cover and chill for up to 1 hour. If mixture is too firm, let stand for a few minutes to soften before piping.
To serve, spoon cheese mixture into a pastry bag fitted with a very large star tip (1/2-inch). Pipe mixture onto assorted small crackers and/or vegetable slices. Makes 1-1/2 cups.