Potluck tip: if prepared in advance, bake as directed, cover and refrigerate for up to one day. Reheat at 325 degrees for 15 minutes covered, then remove cover and continue heating until warm
Preheat oven to 325 degrees. Peel potatoes; cut into ¼ inch slices. Place potatoes in large pot of boiling water. Cook for 5-10 minutes or until tender. Drain well and set aside.
Meanwhile, fry bacon in a large skillet over med-high heat until crisp. Drain on paper towel, crumble and set aside
Add chopped onion to bacon drippings and cook until tender. Stir in flour over low heat and cook to a paste. Add salt and pepper. Add milk and cook until mixture thickens slightly
Arrange half of the sweet potatoes in the bottom of an 11×7 inch baking dish. Sprinkle on half of the crumbled bacon. Pour on half of the milk mixture. Arrange remaining potatoes, sprinkle with remaining bacon and pour the rest of the milk mixture over the top. Sprinkle with cheese. Bake for 20 minutes or until potatoes are tender. If desired, brown cheese for 1-2 minutes under the broiler.
