- 2 pounds red-skinned sweet potatoes (yams)
- 6 tablespoons butter, divided
- 2 pounds carrots, peeled, cut into 1/2-inch-thick slices
- 2 tablespoons (or more) water
- 1/2 cup Sherry wine vinegar
- 1 cup walnuts, lightly toasted
Preheat oven to 400°F. Bake potatoes until tender, about 45 minutes. Cool slightly; peel. Pass through ricer or food mill into large bowl.
Melt 2 tablespoons butter in large pot over medium heat. Add carrots, 2 tablespoons water, and pinch of salt. Cover and bring to boil; reduce heat to medium and simmer until carrots are tender, stirring occasionally and adding more water by tablespoonfuls if dry, about 25 minutes. Add 1/4 cup butter. Use potato masher to mash carrots coarsely. Stir potatoes into carrots. Season with salt and pepper. DO AHEAD Can be made 1 day ahead. Cover and chill.
Stir honey and vinegar in small saucepan to blend. Add walnuts and boil until sauce is thick and syrupy, stirring occasionally, about 10 minutes. Cool slightly. Season with salt.
Rewarm potato-carrot mixture over medium heat, stirring frequently. Transfer to bowl, spoon walnuts with syrup over, and serve.