DIRECTIONS
Sauce Directions:
Mince the garlic, sprinkle with 1/2 tsp. salt and mash with flat side of a chef knife to make a paste.
Transfer to a medium bowl; add the mustard, lemon zest, lemon juice and egg yolk; whisk to combine.
Add the olive oil, then the vegetable oil, whisking constantly until smooth.
Add 1 tsp. water to loosen.
Cover and refrigerate until ready to use.

Broth Directions:
Trim the scallions to about 6 inches; transfer the tops to a large saucepan (set white parts aside).
Trim the fennel and thinly slice; set aside.
Add the celery, carrot, parsley sprigs, bay leaf, peppercorns and 8 cups water to the saucepan.
Bring to simmer; cook 15 minutes.
Strain the vegetable broth into a wide pot.
Add the potatoes and 1 1/2 tsp. salt; bring to boil and reduce to simmer; cook until potatoes are tender.
Transfer potatoes to a bowl with a slotted spoon reserving broth.
Add the reserved scallions, beans and tomatoes to the broth and simmer 5 minutes.

Fish Directions:
Score each fillet crosswise 3 or 4 times on the skin side (do not cut through to the flesh).
Season the flesh side with salt.
Add the fillets to the pot; add the reserved sliced fennel, cover and cook until the fish is just opaque, about 6 minutes.
Divide the potatoes among shallow bowls and top each with a fillet.
Divide the broth and vegetables among the bowls.
Sprinkle with chopped parsley; top each with a spoonful of the sauce.
Serve with crusty bread and the remaining sauce.
Serves 6.