Swiss Chard and Caramelized Onion Lasagna

12 ounces lasagna noodles, uncooked
4 tablespoons olive oil
1 garlic clove, minced
2 bunches red swiss chard, stemmed, coarsely chopped and blanched
1 cup ricotta cheese
salt and pepper
4 1/2 cups onions, thinly sliced
1 teaspoon sugar
1 teaspoon balsamic vinegar
3 cups low-fat milk
1/3 cup flour
1 1/4 cups parmesan cheese, grated or asiago cheese
2 tablespoons parmesan cheese, grated or asiago cheese

Cook noodles just until tender. Cover with plastic wrap and set aside.
In a large skillet, heat 1 tablespoon oil over medium heat. Add garlic and cook, stirring often, about 30 seconds. Add chard and cook, stirring often, until tender, 5minutes. Transfer to a medium bowl and stir in ricotta. Season with salt and pepper and set aside. Wipe out skillet, heat remaining oil over medium heat.
Add onions, cook and stir, until onions begin to brown all over.
Sprinkle with sugar, cook and stir until deep amber in color, about 20 minutes.
Remove from heat and splash with vinegar. In a medium saucepan, heat 2 1/2 cups milk over medium heat until steaming. Put flour in a small bowl and whisk in 1/2 cup milk until smooth; whisk into hot milk and continue to whisk until until sauce simmers and thickens. Cook and stir 1 minute longer.
Stir in parmesan or Asiago cheese until melted and smooth. Season with salt and pepper. Preheat oven to 400 degrees. Lightly oil a 9x13-inch baking dish.
Coat bottom of dish with 1/2 cup sauce. Line bottom with a single layer of noodles.
Spread half the chard over noodles. Add another layer of noodles, arrange onions on top and season with salt and pepper.
Spread another 1/2 cup of sauce over all. Add another layer of noodles, followed by remaining chard.
Finish with remaining noodles and sauce. Sprinkle with remaining Parmesan.
Tightly cover with foil sprayed with cooking spray.
Bake 30 minutes.
Uncover and bake 10-15 minutes, until light brown and bubbly.
Let stand 10 minutes before serving.