Preheat oven to 350F. Spray a 9x5-inch loaf pan with non-stick spray or grease and flour it.

Peel the sweet potatoes and chop into 1-inch chunks. Microwave on high for 15-17 minutes until very fork-tender. Mash with a fork and let cool slightly.

In a bowl, whisk together the mashed sweet potatoes, eggs, oil, buttermilk, and vanilla until smooth.

In a large bowl, whisk together flour, sugars, baking soda, cinnamon, ginger, nutmeg, allspice, cloves, and salt.

Pour the wet ingredients into the dry ingredients and stir until just combined; do not overmix.

Pour the batter into the prepared loaf pan, smoothing the top. Bake for 60-70 minutes until golden and a toothpick inserted in the center comes out clean.

Allow to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely before slicing.