You can use your powdered food coloring to color your chocolate directly, but I have a different way to add some color to your chocolate candies using powdered food coloring.
I melt my cocoa butter and mix in the powdered food coloring to the desired shade I want. Then I take the colored mixture and using a brush paint the chocolate candy mold with the colored cocoa butter. I then place this into the freezer for about 5 min to let set up. After my painted molds are set up I then pour my melted chocolate into my mold and place the mold back into the freezer. When I unmold my painted chocolates, they have an opaque colored look to them. This technique looks absolutely wonderful with chocolate Easter eggs.
You can find the things I used to do this on the following links.
http://www.shopbakersnook.com/205.html
http://www.shopbakersnook.com/m5_view_item.html?m5:item=83
Thank you for taking the time to read this.
Anne
ShopBakersNook.com