Slowly beat the oil, lemon rind, juice, mustard and parsley into egg (for sauce)
Mix topping ingredients in a second bowl
Line grill pan and lightly brush with oil
Arrange fish on pan.
Spoon on sauce.
Sprinkle with topping.
Grill for 10-15 minutes (not close to grill).
Serve immediately.
Notes
Sue served this with salad plus pita breads flavoured with garlic, parmesan cheese, and olives, but a leafy salad with baked potatoes would serve as well.