Wash and snap off butt ends of asparagus, cut stems into 1/2 inch pieces, set tips aside. Melt cannabis butter in a large lidded saucepan. Add asparagus pieces and onion, stir, cook 5 minutes until onion is transparent and soft. Stir in rice and chicken broth, bring to a boil, cover, simmer 10 minutes. Add asparagus tips, simmer 5 minutes longer. Stir in 1 tablespoon Parmesan cheese, and salt and pepper to taste. Let stand, covered, 5 minutes. Sprinkle with remaining Parmesan.