In a large pot add the milk and butter. Cook over low medium heat just until the butter is melted. Take the pan off the heat and set the pot aside to cool.
In a large skillet melt a little butter, I like to let it melt slowly and kind of brown. While butter is browning place a slice of the brioche bread in the custard letting it sit for about 8-10 seconds on each side.
Place in the warm pan with butter and cook over medium heat for 3-4 minutes per side. Turn the oven on to 200F/93C and place the cooked French toast on a baking tray to keep warm while you cook the rest.
Place a slice of French toast on a plate then spread on a tablespoon of Nutella, next sprinkle on some strawberries then place the second slice of French toast on top to create the sandwich.