Immerse whole kale leaves in boiling salted water for 1 minute. Drain.
Add sesame seeds and chilli flakes and mix well.
Heat 20ml oil in a wok till smoking. Add prawns and fry till white but not cooked through, approximately, 2 minutes. Add garlic, cabbage mix and butter and fry till prawns are cooked approximately, 2 minutes. Add lemon juice and stir. Divide between plates.
Add remaining oil to wok and heat till hot. Add glass noodles and fry till crisp and puffy. Remove with a slotted spoon and drain.