Brioche Dough

Directions

1. 1
   Stir together sugar and milk in a small bowl.
2. 2
   Sprinkle yeast over mixture and let stand until foamy, about 10 minutes.
3. 3
   Stir flour into yeast mixture, forming a soft dough, and cut a deep X across top.
4. 4
   Let starter rise, covered with plastic wrap, at room temperature, 1 hour.
5. 5
   Combine salt, sugar, and hot milk in a small bowl and stir until salt and sugar are dissolved.
6. 6
   Fit mixer with whisk attachment, then beat 2 eggs at medium-low speed until fluffy.
7. 7
   Add sugar mixture and beat until combined well.
8. 8
   With motor running, add in order, beating after each addition: 1/2 cup flour, remaining egg, 1/2 cup flour, about one fourth of butter, and remaining 1/2 cup flour.
9. 9
   Beat mixture 1 minute.
10. 10
    Remove bowl from mixer and fit mixer with dough-hook attachment.
11. 11
    Spread starter onto dough with a rubber spatula and return bowl to mixer.
12. 12
    Beat dough at medium-high speed 6 minutes, or until dough is smooth and elastic.
13. 13
    Add remaining butter and beat 1 minute, or until butter is incorporated.
14. 14
    Lightly butter a large bowl and scrape dough into bowl with rubber spatula.
15. 15
    Lightly dust dough with flour to prevent a crust from forming.
16. 16
    Cover bowl with plastic wrap and let dough rise at room temperature until more than doubled in bulk, 2 to 3 hours.
17. 17
    Punch down dough and lightly dust with flour.
18. 18
    Cover bowl with plastic wrap and chill dough, punching down after first hour, at least 12 hours.