mashed potato, rutabaga, and parsnip casserole with caramelized onions

Ingredients

• Servings: 8
• 7 cups low-sodium chicken broth
• 3 pounds baking potatoes, peeled and cubed
• 1 1/2 pounds rutabagas, peeled and cubed
• 1 1/4 pounds parsnips, peeled and cubed
• 8 cloves garlic
• 1 bay leaf
• 1 teaspoon dried thyme
• 3/4 cup butter, softened
• 3 onions, thinly sliced
• salt and ground black pepper to taste

Recipe

• combine chicken broth, potatoes, rutabagas, parsnips, garlic, bay leaf, and thyme in a large pot. bring to a boil. reduce heat, and cover partially. simmer until vegetables are very tender, about 30 minutes. drain.
• transfer vegetables to large bowl. add 1/2 cup butter or margarine . use an electric mixer, beat mixture until mashed but still chunky. season with salt and pepper. transfer mashed vegetables to a buttered 13 x 9 x 2 inch baking dish.
• melt remaining 1/4 cup butter or margarine in a heavy large skillet over medium-high heat. add sliced onions. saute until beginning to brown, about 5 minutes. reduce heat to medium-low. saute until onions are tender and golden brown, about 15 minutes. season with salt and pepper. spread onions evenly over mashed vegetables. casserole can be prepared up to 1 day ahead. cover and refrigerate.
• preheat oven to 375 degrees f (190 degrees c). bake, uncovered, for 25 minutes, or until heated through and top begins to crisp.