Coulibiac (the step x step)

 See recipe in part deux! and have all parts ready.
 Roll brioche into 2 very thin rectangles, about 12" x 20", and place one on parchment lined sheet pan. Then, do below to the one on the pan.....

Then, top with layer of raw baby spinach and top
that with the filets of salmon, then see below, add small butter pats. Top with another layer of baby spinach, another pipe of mousse down the whole shebang.

Egg wash around whole thing and top with other rectangle of dough. Slit tiny vents all the way down. press sides of brioche together all around to press out any air
pockets.

Slice off extra dough and make it look pretty. Seal all the edges together very well. You can cut out shapes or stripes to glue on top, or make a tail. Then, you can bake (again see part deux!) or put in fridge for later baking that day.

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