Apple Gratin

12 Tbsp. Earth Balance margarine
2 lbs. onions, sliced
2 Tbsp. chopped fresh thyme
4 tsp. fine sea salt, divided
2/3 cup water
2/3 cup dry white wine
4 tsp. sugar
2 1/2 lbs. Yukon Gold potatoes, peeled and cut into 1/4-inch-thick rounds
2 lbs. Braeburn or Pink Lady apples, peeled, halved, cored, and cut into 1/4-inch-thick slices

• Preheat the oven to 400°F.
• Lightly oil a 13 x 9 x 2-inch glass or ceramic baking dish.
• Melt 6 Tbsp. of the Earth Balance in a large nonstick skillet over medium heat. Add the onions, thyme, and 2 tsp. of the salt. Sauté for approximately 10 minutes, or until the onions are translucent.
• Increase the heat to medium-high. Sauté an additional 8 minutes, or until the onions are tender and begin to color. Remove from the heat. Add the remaining butter, the water, wine, and sugar. Stir and swirl to combine. Bring to a boil, then cool until lukewarm.
• Combine the potatoes, apples, the remaining salt, and the onion mixture in a large bowl and toss gently to blend. Transfer to the prepared baking dish, spreading evenly. Cover with parchment paper, then cover with tin foil, placing the shiny side down.
• Bake for approximately 55 minutes, or until the potatoes are tender. Uncover and bake an additional 20 minutes, or until the top browns and juices bubble thickly. Let stand for 15 minutes before serving. (The gratin can be made 6 hours ahead of time and left to stand uncovered at room temperature. Then, reheat by loosely covering with foil and warming at 300°F for 20 minutes.)

Makes 8 to 10 servings