Preheat oven to 375 degrees. Cook jumbo shells according to package directions. Drain and let slightly cool. In the same stock pot, heat oil to medium-high heat. Add 2 cloves garlic and saute 30 seconds, until fragrant. Whisk in butternut squash puree and cream or milk and bring to a simmer for 5-10 minutes, stirring frequently. Season with a generous pinch of salt and pepper. If lumpy, use an immersion blender to puree. Stir in ¼ cup Parmesan. Taste and adjust seasoning, if necessary. In a medium mixing bowl, stir together ricotta, kale, ¼ cup parmesan, ½ cup mozzarella, 3 cloves garlic, Italian seasoning, salt and pepper, until combined. Spread a half cup of butternut squash sauce onto the bottom of a greased casserole dish. Stuff each shell with a few tablespoons of ricotta mixture, then layer them on top of the butternut squash sauce. Top shells with remaining butternut squash sauce, then cover with remaining 1 ½ cups mozzarella cheese. Bake 15-20 minutes, until cheese is melted and bubbly. Top with parsley and serve.