Use a heavy-duty knife or sharp kitchen shears to cut verbena stem in pieces about 3 inches long. Layer verbena in bottom of a glass container large enough to hold all the sugar. Pour about half the sugar into the container. Stick split vanilla beans into sugar at even intervals. Add remaining sugar. Seal jar tightly and store at least 1 week before using. Once sugar is aromatic, remove verbena and vanilla. If sugar becomes hard or clumped, break pieces with a wooden spoon and sift before using. Makes 4 cups sugar.

*Kitchen Tip: If verbena is unavailable, substitute peel from one lemon and one 8-inch stalk of mint.