Kale Pasta Bake

I don't have much of an intro for this dish. It's a great way to incorporate kale into your dinners. This pasta bake doesn't have a long list of ingredients or require you to make a sauce. It's just mixed up cooked pasta, chicken, ricotta, and a few other things. Despite the few ingredients it was quite tasty and we both would recommend it to you!

Martha Stewart's Chicken and Kale Casserole
   Prep 25 minutes | Total time 1 hour 15 minutes | Serves 8

Ingredients
Coarse salt and ground pepper
3/4 pound large pasta shells - we substituted rotini
2 tablespoons unsalted butter
1 large yellow onion, diced medium
3 garlic cloves, minced
2 bunches kale (1 1/2 pounds), tough stems and ribs removed, leaves coarsely chopped
2 cups shredded or chopped cooked chicken (from 1/2 rotisserie chicken)
     we baked two chicken breasts beforehand
1 container (48 ounces) part-skim ricotta
3 tablespoons finely grated lemon zest (from 2 lemons)
3/4 cup Parmesan, grated (2 1/4 ounces)

Directions
   Preheat oven to 350 degrees. In a large pot of boiling salted water, cook pasta according to package instructions. Drain; return to pot. In a large skillet, melt butter over medium-high. Add onion and garlic; cook until onion is beginning to soften, 4 minutes. Add kale, cover, and cook until almost tender, about 5 minutes. Transfer to pot with pasta.
   Stir in chicken, ricotta, lemon zest, and 1/2 cup Parmesan; season with salt and pepper. Transfer mixture to a 9-by-13-inch baking dish; top with 1/4 cup Parmesan. Bake until top is golden, 30 minutes.