Preheat oven to 350 degrees F. In a small bowl mix a few drops of water and a few drops of green food coloring. Add the coconut, and toss until all of the coconut is tinted green. Set aside.
Place the vanilla wafers, flat side up, on an ungreased baking sheet, and place one mint patty on each of the vanilla wafers, and place in the oven for about 1 minute, or just until the chocolate begins to soften; remove from the oven, and sprinkle each with 1/2 teaspoon tinted coconut, and top with another vanilla wafer, flat side down, and press gently.
Using your finger, dab the top of each vanilla wafer with just enough water to moisten, and sprinkle with a few sesame seeds.