Stir the egg white, cornflour, white pepper and ginger together in a bowl; add the basa and mix to coat. Set aside and allow to marinate at least 15 minutes.
Heat 1 tablespoon vegetable oil in a frying pan over medium heat; cook and stir the peppercorns and dried chillies in the hot oil until they turn a very dark red (they will look almost black, so be careful not to burn the chillies). Remove the dried chillies and peppercorns from the frying pan. Mince the chillis. Mash the peppercorns finely; set aside.
Return the frying pan to the medium heat and add 1 tablespoon vegetable oil and the bean sauce; cook and stir the bean sauce with the oil until the mixture turns red. Stir the water into the sauce, increase heat to high then cook until the sauce simmers. Remove the ginger slices from the marinating fish and add to the boiling sauce; cook the fish at a boil until the flesh turns white.
Divide the celery and cabbage between two soup bowls. Pour the fish and sauce over the celery and cabbage. Top with the garlic, peppercorns and chillies.
Heat 1 tablespoon olive oil in a frying pan over high heat until it just begins to smoke; carefully pour the hot oil over the garlic, peppercorns and chilli. Garnish each portion with coriander to serve.