Created by Derf on October 15, 2011
Step 1: In a saucepan melt butter over medium heat, add flour, salt, pepper and thyme, cook, stirring for 1 minute
Step 2: Gradually whisk in milk, cook, whisking constantly until thickened, 5 to 8 minutes; remove from heat and add 1 cup of shredded cheddar, stir to mix well; set aside
Step 3: Peel or scrub the potatoes well and leave peal on, thinly slice; (I use the slicer on my food processor; makes it quick and uniform slices, I also slice the onions with the food processor).
Step 4: Layer one third potatoes in an 9 inch x 12 inch buttered glass baking dish; spread with half of the onions, repeat layers, arrange remaining potatoes over top; pour sauce over top; if necessary lift potato onion layers to let the sauce drip through.
Step 5: Sprinkle the remaining 2 cups shredded cheddar evenly over the top
Step 6: Cover tightly with foil and bake in 350F degree oven for 1 hour
Step 7: Uncover and bake for 30 minutes or until lightly browned and potatoes are tender. Let stand for 5 minutes before serving