Cook Sausage Preheat oven to 350°F. In a 10-inch skillet cook sausage and onion over medium-high until meat is browned; drain off fat. Return to skillet; stir in kale.
Cook Pasta Meanwhile, cook lasagna noodles according to package directions; drain. Rinse with cold water; drain and cool slightly.
Make White Sauce For sauce, in a medium saucepan melt butter over medium. Add garlic; cook and stir 1 minute. Stir in flour, salt, and pepper. Gradually add milk; cook, stirring constantly, until thickened and bubbly. Remove from heat; stir in ¼ cup of the Parmesan.
Assemble Spread ¼ cup of the sauce in a 3-qt. rectangular baking dish. Arrange three of the cooked noodles lengthwise over sauce in dish. Spread one-third of the ricotta over noodles. Top with one-third of the sausage mixture, one-fourth of the remaining sauce, and one-third of the provolone. Repeat layers two more times, starting with noodles and ending with provolone. Top with the remaining three noodles and sauce. Top with the remaining ¼ cup Parmesan.
Bake Bake until bubbly and heated through, 45 minutes. If you like, sprinkle with additional Parmesan. Let stand 15 minutes.
