Place flours, baking powder, baking soda, and salt in a bowl and stir until well mixed.
Place spices and brown sugar in a bowl; add eggs and orange juice beat until smooth. Stir in canned pumpkin and oil.
Stir flour mixture into pumpkin mixture until just combined.
Stir together topping ingredients until well mixed. Spoon a little on top of each muffin, or spread equally over the loaf.
For muffins, place cupcake liners in a muffin tin. Divide batter equally and top with sugar-spice mixture. Bake for 20 minutes.
For a loaf, line a loaf pan with parchment paper and fill with mixture, then add topping evenly across the top. Bake on middle rack of oven for 50 to 55 minutes or until a toothpick (or spaghetti!) inserted in centre comes out clean. Let pan cool on rack for 15 minutes; turn loaf out and let cool completely.