Place oysters in a bowl with water and the preparation salt and potato starch. Gently wash, replacing water twice, and pat dry. Season with salt and pepper, then coat with flour.

Cut pea shoots in half and trim the roots. Slice green onion diagonally into 7mm pieces. Slice two thin rounds of lemon and squeeze the rest.

Heat olive oil in a pan over medium heat. Add oysters and cook until browned, flip, cover, and steam for 1 minute on low heat. Remove from pan.

In the same pan, sauté green onion until softened. Add half of the pea shoots and stir-fry briefly. Season with salt, then turn off heat and mix in the remaining pea shoots. Plate the mixture.

In the pan, add lemon slices, lemon juice, butter, and soy sauce. Heat on low until bubbling, then season with salt and pepper to taste.