Onion Mashed Potatoes

This is a recipe I got from Ellen Palsson (Craig's mom, for those who know them)

Sweet Onion Mashed Potatoes

6 tablespoon butter
2 cups chopped sweet onions (such as Walla Walla or Vidalia)
2½ pounds russet potatoes, peeled and quartered
1 cup milk
¼ teaspoon salt


In a small saucepan, melt butter and gently sauté chopped onions over medium-low heat for 25 to 30 minutes, or until the onions have softened and turned a rich golden brown; set aside.
While onions are cooking, boil potatoes in a large pot of salted water until tender, 15 to 20 minutes. Remove from heat, drain well and mash thoroughly with a potato masher.

To the onion mixture, add milk and salt and warm gently, then whisk into potatoes; adjust seasonings and serve.