Place water in a small bowl and sprinkle gelatin over the top; let sit.
Heat coffee, sugar, and cinnamon in a small saucepan; stir until sugar is dissolved. Off heat, pour in the gelatin mixture and stir until combined. Pour into a 9 x 13-inch baking dish and refrigerate until set. Slice into 1-inch cubes and place enough in a glass to fill halfway. Pour macadamia milk over the jellies before serving.