FIG. 1 is a top perspective view of a cocktail strainer showing my new design. FIG. 2 is a bottom perspective view thereof. FIG. 3 is a rear view thereof. FIG. 4 is a front view thereof. FIG. 5 is a right side view thereof, the opposite side being a mirror image. FIG. 6 is a bottom plan view thereof; and, FIG. 7 is a top plan view thereof.