Preheat a convection oven at 380°F. Take the temperature of the flour and the temperature of the room. Subtract the total of these two temperatures from the base temperature. The number left is the temperature your milk should be. Adjust your milk temperature appropriately.
Example: The temperature of the room is 73 °F and the temperature of the flour is 68°F. 73 + 68 = 141. 200 (base temperature) – 141 = 59. In this example the milk temperature should be 59°F.
Make a polish by mixing the milk with the yeast in a mixing bowl. Cover this mixture with the pastry flour and let ferment until cracks form on the surface of the flour. It is very important not to disturb the polish. Add the salt, sugar, bread flour, and eggs to the polish. Mix on medium speed until the dough is elastic and wraps around the hook. This should take 5-10 minutes, depending on the amount of dough you are preparing. The final product will have a shine and you should be able to stretch it “see-through thin.” Add half of the mixture in slow gear until incorporated (2-3 minutes). Add the remaining mixture in medium gear (4-5 minutes). Place the dough in a bowl, dust with flour and cover with plastic wrap. Let the dough double in volume in a warm place (81°F). Press out the first gasses and place the dough in the cooler for at least 2 hours. Press out the second gasses after 2 hours and let the dough rest in the cooler overnight. When you shape the brioche do not use too much flour or else it will not stick to the table and form a tight seal on the bottom. Shape 40 brioche balls and place them in buttered molds. Lightly egg wash by mixing egg, milk and salt over the brioche balls. When you are egg washing, you need to wipe all the excess egg wash off the brush so it does not drip down your product. It is best to egg wash with a soft bristle brush so you do not damage the dough. Egg wash prior to proofing so a skin does not form on the top of the dough. Let the brioche proof until it doubles in volume. Bake in the oven for approximately 14 minutes for a 3-4 ounce piece with the vent closed for the first part of baking. For the last 5 minutes open the vent so the steam escapes and the final product will be lighter. If your oven is too hot, the product will brown too quickly and it will be hard to tell when it is done. You can insert a knife (the same direction that you would cut a slice) and hold it in there for 2 seconds. Remove the knife; if there is no residue on the blade the brioche is done.