Preheat the oven to 350 degrees F., and grease two 9x5-inch loaf pans well. Set aside.
In a large bowl, add the sugar, eggs, and oil, and mix well to combine.
Add the the mashed sweet potatoes and vanilla, and stir to combine.
Add the flour, baking powder, nutmeg, allspice, cinnamon, salt, and baking soda. Stir to combine.
Fold in the pecans.
Divide the batter evenly between the two prepared pans, and smooth out the top.
Bake for 60 to 70 minutes, or until the center is set and toothpick interested in the middle comes out clean.
Let the bread cool on a wire rack for 10 minutes, and then run a knife along the edge to remove from the pan and finish cooling on a cooling rack.
Serve warm or at room temperature.
Notes
For a lighter version, replace the 1 cup of oil with 1/2 cup oil and 1/2 cup applesauce OR 1 cup applesauce. It works great with those substitutions.
Omit the nuts if you like, but they are SO good in this bread.
This bread freezes very well.
If you can make banana bread (which everyone can!), then you'll ace this homemade sweet potato bread recipe that's so simple and tastes like a treat even though there's a veggie superfood inside! But don't worry, it tastes like cake.