Traditional Newfoundland Cod au Gratin

INGREDIENTS

1 1/2 lb

cod (-about 3 large fillets, cut into bite sized pieces)

2 cups

milk

1 tbsp

olive oil

onion (-minced)

4 tbsp

unsalted butter (-1/4 cup)

4 tbsp

all purpose flour

1 1/4 tsp

salt (-divided)

1/2 tsp

black pepper

1 tbsp

lemon zest (-reserve lemon for wedges (4) later)

1 3/4 tsp

dried dill (-divided)

2 cups

shredded cheddar cheese

croissant (-made into bread crumbs or 1 cup bread crumbs)