The ornamental design for a barbecueutensil, as shown and described.
FIG. 1 is a perspective view of the barbecue utensil of the present invention showing my new design with the dotted lines solely depicting environmental structure and forming no part of the claimed design;
FIG. 2 is a top plan view thereof;
FIG. 3 is a left side elevational view thereof;
FIG. 4 is a front elevational view thereof;
FIG. 5 is a bottom plan view thereof;
FIG. 6 is a right side elevational view thereof; and,