The Okinawan sweet potato is a very special potato. It doesn't look like much from the outside (<a href="http://labofedibles.wordpress.com/2007/12/13/the-ugly-duckling-okinawan-purple-sweet-potato/">This site</a> calls it the ugly ducking of potatoes), but it is one beautiful and delicious spud! <p> This pie is a mixture of recipes from <a href="http://onokinegrindz.typepad.com/ono_kine_grindz/2004/10/okinawan_sweet_.html">Reid at Ono Kine Grindz </a> and my family's special shortbread recipe. <p> I would not use any other potato for this recipe. It IS labor intensive, but the pay off is so worth it! This should be a smooth, rich, mouth-watering treat. People always ask me to make this for them.<p> Cooking time does not include overnight refrigeration.