Preheat oven to 350° (F). Grind allspice berries in mortar.
In large bowl, beat eggs and then whisk in sugar. Add pumpkin puree and mix well.
Add molasses, evaporated milk, allspice, cinnamon, ground ginger, pumpkin pie spice, and baking powder, and stir it all in.
Add toasted oat flour and all-purpose flour and mix in thoroughly. Melt butter and mix in.
Optional: Add chopped walnuts and stir to distribute evenly.
Grease 9”x5” loaf pan (I use Baker’s Joy Cooking Spray) and fill with batter. Bake at 350° (F) for 45 minutes or longer, until done (toothpick comes out clean).
Glaze Preparation
In pot over medium heat, melt butter. Add maple syrup and confectioner's sugar, and whisk in thoroughly.