I typically associate mousseline with brioche that is baked in a tall cylinder mold with a parchment collar, so that it rises above the mold. It is then sliced and used for canapés, and the leftovers can be used to make Bostock, that delicious syrup-imbibed, almond cream covered, twice baked delight.
Brioche Nanterre is another version in which dough balls are lined up in a loaf pan, proofed and baked so the balls essentially fuse together, creating a "pull-apart" look.
Since Philippe's recipe instructs the Nanterre type of line up, I was intrigued by his use of the word mousseline. My research revealed that the word has several meanings, depending on its context. In the culinary world it is a sauce, such as a hollandaise, to which butter is added, whereas in the pastry world it is crème pâtissière to which butter is added.
In this brioche recipe it has to do with the flour to butter ratio. A classic "medium" brioche has a 2:1 flour to butter ratio, whereas a brioche mousseline has closer to a 5:4 flour to butter ratio. So that's what makes Philippe's recipe a mousseline. In a word - butter!! Some call this "Rich man's brioche" due to the high butter content.
Now on to the process!
When making brioche dough, use a heavy duty stand mixer. I generally plan on anywhere from 20-30 minutes of mixing time, so it's helpful to have a number of minor tasks you can perform while waiting for the process to finish. Just be sure you keep on eye on your mixer, because it can start "walking" around your counter during the butter addition.
This recipe is straight forward. Have your cool butter diced and ready to go. Mix flour, sugar, salt and yeast in the bowl of your stand mixer. Starting out with the paddle (NOT the dough hook), add the eggs and mix on low speed until the dough comes together. Then continue mixing on medium speed for up to 10-15 minutes until the dough becomes very elastic and starts to clean the sides of the bowl.
|diced butter ready to be added|
|the dough can really creep up the hook!|
|after butter addition, ready for a rest|
Cover it with plastic film and let it rest 1.5 hours at room temp.
Then place the dough on a lightly floured surface, form a rough ball, wrap in plastic and refrigerate for 3 hours.
|dough after room temp rest|
|rough ball ready to be wrapped and chilled|
After the chill time (in which the dough becomes quite firm), remove the dough from the fridge and get ready to shape!
|chilled dough ready to be divided|
Then shape each piece into a boule.
Have a buttered loaf pan ready and place the boules snugly into the pan.
|ready for the final two hour rise|
|"fused" together after the rise|
|fresh out of the oven|
|sliced and ready to taste|