Preheat the oven to 325°F (163°C). Grease two 8.5 x 4.5-inch loaf pans or line with parchment paper.
In a large bowl, beat the eggs until frothy. Add the pumpkin puree, canola oil, melted butter, brown sugar, and vanilla. Mix until smooth.
In a separate bowl, combine the flour, granulated sugar, instant pudding mix, baking soda, cinnamon, baking powder, salt, and nutmeg. Whisk to blend.
Gradually add the dry ingredients to the wet ingredients and mix until just combined.
Divide the batter between the loaf pans and smooth the tops. Sprinkle with cinnamon-sugar topping if desired.
Bake for 60-70 minutes or until a toothpick inserted in the center comes out clean.
Let the loaves cool in the pans for 10 minutes, then transfer to a wire rack to cool completely before slicing.