Make pasta according to directions on the back of the package.
Melt 2 tbsp of butter in a small skillet. Toss breadcrumbs in butter to coat them. Set aside in a bowl.
Melt remaining butter in a small sauce pan. Add onions and cook for 1-2 minutes or until softened. Add salt, pepper, paprika and stir to combine. Cook for 1 minute over medium-low heat.
Add milk to sauce pan and bring to a simmer. Stir frequently.
Remove sauce pan from heat and add cheese. Stir until smooth.
Combine pasta, kale, and cheese sauce in a large mixing bowl. Place mixture into a large baking dish and top with breadcrumbs. Bake at 400 degrees for 15 minutes, or until breadcrumbs turn golden brown.