For the pike-perch with olive-herb crust, grate toast bread into fine crumbs (or grind in a food processor). Mix toast crumbs with parsley, thyme and chopped olives.
Fold in cream, egg white and lemon juice until well moistened. In a frying pan, brown the butter and extinguish with the lemon juice, cook briefly. Season with salt and cayenne pepper.
Cut pike-perch fillets diagonally into evenly sized pieces. Coat pike-perch with mustard and sear briefly on both sides. Carefully brush olive mixture about 5 mm thick onto fillets. Place zander fillets on an oiled baking tray. Bake in oven preheated to 180 degrees for 5-7 minutes.
Arrange pike perch with olive-herb crust with any garnish and serve.