Preheat oven to 350 degrees
Place the dates and water in a saucepan on the stove and heat on low.
Meanwhile, combine the softened butter, oil, slurp, and egg in a mixing bowl.
Add the ground millet, oats, arrowroot flour, and xanthan gum.
Combine until well mixed then divide the dough into two halves. Place half of the dough into a lightly oiled 9x9 inch baking dish and spread out until it covers the bottom. Set the other half to the side.
Blend the dates and water in a blender until there is a nice puree. Spread it over the dough in the 9x9 pan.
Take the remaining dough and place small balls of it across the filling, Don't worry, they will bake together and form a crust. Top with walnuts and bake at 350 for about 20 minutes.