Place your design under a piece of acetate. Mix a few tablespoons of the cocoa butter with a small amount of powdered food color. Use a fine-tipped paintbrush to trace the outline of the design with a dark-colored paint. Use other paint colors to fill in the design. Allow the paint to dry.
To make a raplette, Jacques Torres creates a homemade chocolate spreader by using poster board and an X-Acto knife. Since his painting is 10-inches by 16-inches, the opening he will cut in the raplette is 10-inches wide by 1/8-inch high. Pour some white chocolate at the edge of the painted acetate. Pull the raplette through the chocolate, pulling the chocolate over the painted drawing. This will spread an even 1/8-inch thick layer of white chocolate over the painting. When the chocolate begins to set, use a sharp paring knife to cut the paint canvas to the finished size of the painting. Let this cool until the chocolate sets. When the chocolate has set completely, simply peel off the acetate.
To make the frame, use an offset spatula to spread a 1/4-inch-thick layer of tempered chocolate over a sheet of acetate. Let the chocolate set slightly. Use a paring knife to cut 2 pieces of chocolate that are 16 inches long and 2 inches wide. Cut two more that are 12 inches long by 2 inches wide. When the chocolate is set, peel off the acetate. Use a mitre box to trim all 4 ends to 90 degree angles. Just use a gentle sawing motion to cut through each piece. Use tempered chocolate to glue the frame pieces to the outside of the painting. Use vegetable oil to glaze the frame to make it shiny.