Canadian Baked Fish and Potato Casserole

Jump-start dinner with leftover cooked potatoes — layered with onions, a creamy sauce, flaky pickerel, and finished with a crisp panko topping — and have this casserole on the table in under an hour. And most of that is baking time, so no babysitting required!


  • 4 skinless Canadian pickerel, halibut, or other whitefish fillet portions (150 g / 0.33 lb each; total 600 g / 1.32 lb)
  • 4 cooked large yellow-fleshed potatoes, peeled, sliced into ¼-inch thick rounds
  • 1 onion, thinly sliced
  • 2 tbsp (30 g) butter, divided
  • 2½ cups (625 mL) homogenized (3.5%) milk
  • 3/4 cup (68 g) freshly grated Parmesan cheese, divided into ¼ cup (about 23 g) and ½ cup (about 45 g) portions
  • 3 tbsp (24 g) all-purpose flour
  • 1 tbsp (15 g) Dijon mustard
  • A pinch of fine herbs or ground poultry seasoning
  • ½ tsp (4 g) each salt and pepper
  • ½ cup (60 g) panko breadcrumbs
  • Chopped fresh parsley to garnish


  1. Grease 11x7-inch (2 L) baking dish. Layer potatoes and onions in bottom of dish; dot with 1 tbsp (15 g) butter.

  2. In a bowl, whisk together milk, ½ cup (23 g) of the cheese, flour, mustard, fine herbs, salt and pepper until smooth; pour all but ½ cup (125 mL) over potato mixture. Arrange fish over top; spoon remaining milk mixture over fish. Cover with foil.

  3. Bake in preheated 400° (200°C) oven for 20 minutes.

  4. Meanwhile, in a small bowl, melt remaining butter in microwave on HIGH for 15 seconds. Mix in panko crumbs and remaining cheese; toss to moisten.

  5. Remove fish from oven; uncover and sprinkle top of casserole with panko mixture. Bake, uncovered, until bubbly and golden, about 15 minutes. Sprinkle with parsley, if desired.

Chef's Tip

  • Don’t have cooked potatoes? Simply prick 4 large raw potatoes all over with a fork, place on a microwave-safe plate and microwave on high for 5 minutes. Turn over and microwave for another 2–4 minutes until fork-tender.
Species Icons White Pickerel

Health Benefits of Pickerel

  • Bone & Teeth Health: Pickerel is naturally a good source of vitamin D and phosphorous, which have a factor in the formation and maintenance of strong bones and teeth.
  • Brain & Antioxidant Defense: As an excellent source of selenium and a source of omega-3s, pickerel may support the normal physical development of the brain, eyes and nerves primarily in children under two and provide potent antioxidant protection against oxidative stress.
  • Energy & Growth: As an excellent source of thiamine and Vitamin B12, and a good source of riboflavin and niacin, pickerel may promote energy metabolism and aid normal growth and development while also supporting red blood cell formation.