Line a 13 by 17-inch cookie sheet with sides with plastic wrap.
Melt the chocolate. Add the remaining ingredients, stir well, and scrape into the prepared pan. The mixture should be about 1 inch thick in the pan; it will not fill the pan entirely. Cover and let set overnight at room temperature; the mixture will be stiff but still flexible.
Turn the candy out onto a work surface and peel off the plastic wrap. Cut into 3/4-inch wide strips, then use your hands to "scrunch" each strip into a log. Roll the logs thin between your hands (or on the work surface) until they are about 1/2-inch in diameter. Cut into 1-inch long sections. Set aside to firm up a bit before wrapping or serving (the mixture warms up and softens as you handle it).
Roll each candy up in a square of colored foil or cellophane, twisting the ends to secure. You can also form the modeling chocolate into leaves, roses, ropes for initials or animals.