The ornamental design for a cookingdevice, as shown and described.
FIG. 1 is an isometric view of my design.
FIG. 2 is a front elevational view of the design of FIG. 1, the rear elevational view being the same as the front elevational view.
FIG. 3 is a right side elevational view of the design of FIG. 1, the left side elevational view being the same as the right side elevational view.
FIG. 4 is a top plan view of the design of FIG. 1; and,
FIG. 5 is a bottom plan view of the design of FIG. 1.
The broken lines in these drawings serve to illustrate the environment in which the claimed design is associated. The broken lines form no part of the claimed design.