Combine yeast, sugar and warm water and let set for 5 minutes.  Add olive oil.  Mix 1 cup of the white flour, and 1 cup of the whole wheat flour with the yeast mixture and knead until dough becomes soft and pliable. Add remaining flour if too sticky to touch, but only enough to allow the dough to be pliable and not sticky. Let dough rise, in a warm place, for about 30-45 min., until double in size.

Roll out a small portion of the dough at a time, cutting two equal sized hearts with a cookie cutter. Fill middle with filling, thin layer marinara sauce, cheese, and spinach, and then crimp edges with a fork. Set on baking tray. Bake at 425 for 10-15 minutes until lightly browned. Test to make sure dough is done baking. Serve with marinara sauce for dipping.