Preheat oven at 225C.
Heat the oil in a frying pan.
Add the spring onions & season with salt & pepper. Cook for 4 minutes over medium heat, stirring occasionally.
Add the flour & mix well. Cook for 1 minute, stirring consistently.
Slowly add the stock & besciamella sauce, stirring as you add.
Bring to boil, add the chives, stir & then let simmer for 5 minutes.
Put aside ¼ of the sauce. Add all the fish to the pan. Bring to boil & simmer for 10 minutes.
While waiting for the sauce to simmer, prepare the crepes. Mix the crepe mixture with the milk slowly, whisking as you add the milk. Whisk until you have a smooth mixture.
Spray a frying pan with baking spray.
Heat up the pan. Pour some of the mixture & move the pan in circular motions to spread the mixture evenly in the pan. Cook until golden on each side. Set them aside. You should end up with approximately 15 crepes.
When everything is cooked, start assembling the crepes in an oven dish. Spoon some seafood mixture in a crepe & roll it closed. Set them one by one next to each other in the oven dish.
When done assembling, top the crepes with the sauce that you had saved prior & then sprinkle the breadcrumbs on top.
Cook in the oven for 10 minutes.