See source link for information: Handbag mold Transfer sheets
To make the sides of the handbag, use a ladle to fill one of the side mold pieces with bittersweet chocolate. When it is full, empty the excess chocolate back into the bowl. The inside of the mold should be evenly coated with chocolate. Wipe the lip of the plastic mold clean and place upside down on a wire rack over a sheet pan. Repeat using the other side of the mold. Once the chocolate starts to harden, about 5 minutes, scrape the lip of the mold clean again with a paring knife. When the chocolate sets, it shrinks or retracts from the sides of the mold, and a clean edge will keep it from sticking and cracking as it shrinks. You can place the mold in the refrigerator for several minutes to help the chocolate to harden.
If the chocolate is properly tempered, it will easily release from the mold. To unmold, rest your thumbs on the outside, place your first two fingers on the inside of the bag and gently begin to lift the chocolate from the mold. Do not press or pull too hard or you will break the chocolate. You will need to apply this lifting pressure to all sides to loosen the chocolate from the mold. Repeat for all of the mold pieces. To make the body, use an offset spatula to spread a layer of chocolate onto the square textured plastic pieces of the handbag mold set. Be careful not to make it too thin or it will break when you bend it. Allow the chocolate to set slightly. Place each of the molded side pieces at one end of the square and carefully wrap the rest of the square up the side pieces.
When the chocolate has set, carefully peel away the plastic sheet. It should release from the chocolate quite easily. When you are ready to close the handbag, repeat the same procedure using the other flat textured piece. Be careful that you do not make this piece until after you have filled the bag with the desired contents. The handle is made using the same technique. To make the label, place a transfer sheet in front of you. Mix a little bit of red food coloring into the melted cocoa butter. Using a small pastry brush, apply a light layer of color to the transfer sheet and allow it to set briefly. Using an offset spatula, spread approximately a 1/4-inch thick layer of white chocolate over the color onto the transfer sheet, completely covering the design. Allow the chocolate to set. When the chocolate has set, carefully peel away the back of the transfer sheet. It should release from the chocolate quite easily. Using a hot, sharp chef's knife, cut out a label. To do this, heat the knife under very hot water and wipe it dry. Hold the knife blade against the side of the chocolate where you want to make the cut. Do not press on the knife or the chocolate will break. Allow the heat of the knife to "cut" through the chocolate by melting it. Repeat to make as many labels as required. Set aside until ready to use. Carefully fill the handbag with the desired filling. Attach the piece that closes the bag (as described above). Use tempered chocolate to "glue" the handle and label to the front.
How to Temper Chocolate(From Dessert Circus, Extraordinary Desserts You Can Make At Home by Jacques Torres): Chocolate is tempered so that after it has been melted, it retains its gloss and hardens again without becoming chalky and white (that happens when the molecules of fat separate and form on top of the chocolate). There are a variety of ways to temper.
One of the easiest ways to temper chocolate is to chop it into small pieces and then place it in the microwave for 30 seconds at a time on high power until most of the chocolate is melted. Be very careful not to overheat it. (The temperature of dark chocolate should be between 88 and 90 degrees F, slightly warmer than your bottom lip. It will retain its shape even when mostly melted. White and milk chocolates melt at a temperature approximately 2 degrees F less because of the amount of lactose they contain.) Any remaining lumps will melt in the chocolate's residual heat. Use an immersion blender or whisk to break up the lumps. Usually, chocolate begins to set, or crystallize, along the side of the bowl. As it sets, mix those crystals into the melted chocolate to temper it. A glass bowl retains heat well and keeps the chocolate tempered longer. Another way to temper chocolate is called seeding. In this method, add small pieces of unmelted chocolate to melted chocolate. The amount of unmelted chocolate to be added depends on the temperature of the melted chocolate, but is usually 1/4 of the total amount. It is easiest to use an immersion blender for this, or a whisk.
The classic way to temper chocolate is called tabliering. Two thirds of the melted chocolate is poured onto a marble or another cold work surface. The chocolate is spread out and worked with a spatula until its temperature is approximately 81 degrees F. At this stage, it is thick and begins to set. This tempered chocolate is then added to the remaining non-tempered chocolate and mixed thoroughly until the mass has a completely uniform temperature. If the temperature is still too high, part of the chocolate is worked further on the cold surface until the correct temperature is reached. This is a lot of work, requires a lot of room, and makes a big mess.
A simple method of checking tempering, is to apply a small quantity of chocolate to a piece of paper or to the point of a knife. If the chocolate has been correctly tempered, it will harden evenly and show a good gloss within a few minutes.