Dry the prawn well with a paper towel. Marinate the prawn with salt and cooking wine for 10 minutes. Sprinkle cornstarch over the prawns.
Heat a frying pan and cook each side for a minute. Remove and set aside.
Heat butter in a pan until melted. Add mashed salty egg yolk into the melted butter. Mix well with the butter until foamy. Add garlic into the yolks until fragrant. Add back prawns and stir-fry quickly.