Mashed Potato, Rutabaga, and Parsnip Casserole with Caramelized Onions

7 c low sodium chicken broth (or enough to cover the cubed vegetables)

3 lbs potatoes, peeled and cubed

1 ½ lbs rutabagas, peeled and cubed (or 3 lbs rutabaga and omit the parsnips)

1 ¼ lbs parsnips, peeled and cubed

8 cloves garlic

1 bay leaf

1 tsp dried thyme (or 2 tbsp fresh thyme chopped)

¾ c butter, softened

3-4 large onions, thinly sliced

S&P

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 -60 minutes. Drain.
Transfer vegetables to large bowl. Add 1/2 cup butter or margarine. (Or, use less butter and replace with some of the broth used to boil the vegetables) 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. Make sure to cook onions slow and low until they develop a nice rich color – the onions really make this dish. 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. Keep an eye on the casserole around 20 – 25 min, if onions start to blacken cover w/ foil the parts that are getting too dark and let the rest of the top continue to brown.

Alternate idea: Add crumbled bacon to top