2 tablespoons olive oil
1 1/2 pounds peeled raw sweet potatoes, cut into 1-inch chunks
1 large onion, cut into large dice
1 tablespoon butter
1 pinch sugar
3 large garlic cloves, thickly sliced
1 1/2 teaspoons ground ginger
1/2 teaspoon ground nutmeg
1/8 teaspoon cayenne pepper
3 cups chicken broth, homemade or from a carton or can
1 1/2 cups half-and-half (or whole milk)
Salt and freshly ground pepper, to taste
Garnish: chopped honey-roasted peanuts