The lighter and richer Brioche Mousseline dough is perfect for these. They can be baked in a standard loaf pan or in the same type of round pan used for cake layers.

Makes 2 medium loaves

1 batch Brioche Mousseline Dough (see below)

Egg wash: 1 egg well whisked with a pinch of salt, optional

Butter two 8 x 4 x 2 1/2-inch loaf pans. Divide the fully risen brioche dough in half, making two 450-gram pieces. Divide each half into 5 pieces and round them all.
Stretching the dough balls slightly, place 5 pieces of dough in a line in each pan. Don’t worry if the pans aren’t full—they will be once the loaves have proofed.
Cover the loaves with a lightweight flat-weave kitchen towel and let the dough rise until doubled and filling the pan.
Set a rack in the lower third of the oven and preheat to 375°F.
Once the dough has fully proofed, brush it with egg wash if you like, being careful not to let any run between the loaf and the pan, which would make it stick.
Bake the loaves until they are well risen and deep golden, with an internal temperature of 200°F, 30 to 40 minutes.
Unmold the loaves onto a rack and cool them on their sides to prevent them from falling.
Wrap and keep the loaves at room temperature. For longer storage, freeze them; defrost and reheat the loaves briefly at 350°F and cool them before serving.

BRIOCHE MOUSSELINE DOUGH

Makes 2 pounds/900 grams, enough for 2 loaves

2 tablespoons sugar

2 1/4 teaspoons fine granulated active dry or instant yeast

1/3 cup whole milk, scalded and cooled to 100°F

4 large eggs, at room temperature

3 cups unbleached bread flour (spoon into dry-measure cup and level)

1 teaspoon fine sea salt

2 sticks unsalted butter, softened

Stir the sugar and yeast together in the bowl for a stand mixer, then whisk in the cooled milk. Let sit for 1 minute, then whisk again. Whisk in the eggs.
Use a large rubber spatula to stir in the flour, making sure not to leave any in the bottom of the bowl or stuck to its sides.
Using the dough hook, beat the dough on the lowest speed until it comes together but isn’t completely smooth, 2 to 3 minutes. Stop the mixer and let the dough rest for 15 minutes.
Begin mixing again on low-medium speed and sprinkle in the salt. Add the butter in 8 or 10 separate pieces, then let the dough mix until it completely absorbs the butter and becomes smooth, shiny, and elastic, about 5 minutes. If the dough doesn’t absorb the butter easily, stop and scrape down the bowl and dough hook every couple of minutes. Once you see that the butter is on its way to being completely absorbed, increase the speed to medium for about 1 minute.
Scrape the dough into a buttered bowl, turn it over so that the top is buttered, and cover with plastic wrap. Let the dough ferment until it doubles in bulk, 1 to 2 hours, depending on the temperature.
Once the dough has fermented, scrape it onto a floured surface and give it a turn: Press the dough into a fat disk and fold one side over the center, then fold the other side over both. Roll the dough down from the top to form an uneven sphere. Place the dough back in the bowl (butter the top again if necessary) seam side down and cover it again.
Refrigerate the dough for a couple of hours or until it rises again and then chills down. It’s now ready to us. You can leave the dough in the refrigerator overnight, but you should bake it within 18 hours of beginning to mix it.