Remove the tips of the asparagus and set aside. Cut the stems into bite-size pieces and set aside.
Mix the butter and flour together in a small bowl and set aside.
Season the chicken with salt & black pepper. Heat the oil in a large non-stick frying pan. Gently fry the chicken until brown.
Add the onion and garlic and cook until soft (about 5 minutes).
Pour over the stock, and bring to a gentle simmer. Cook for 5 mins, then the cream and flour mixture. Mix until the flour mixture dissolves into the sauce. Add the asparagus stems and parsley and cook for 2 minutes.
Add the aspargus tips and cook another minute (Thicker asparagusmay need to cook longer so cooking times may vary).
Taste for seasoning and season with salt & pepper as needed before serving. Serve on rice or with the side of your choice.