Sift together the dry ingredients and place in a mixing bowl. Combine the honey, butter, milk and eggs, and mix into the dry ingredients. . Fold in the cubed sweet potatoes, pour batter into a well-greased 8 inch by 8 inch by 2 inch baking dish and bake in a hot oven, 400 degrees, for 1 hour. Cut into squares and serve hot, with lots of butter.