1. Place warm water and milk in bowl of mixer. Add yeast and sugar and stir to combine.
2. Switch to dough hook and add in flour (all but one cup) and salt. Mix at medium-low speed until the mixture resembles shaggy, crumbly lumps.
3. Add vanilla and then eggs, one at a time, mixing until well blended after each addition.
4. Increase speed to medium and beat until dough is smooth, about five minutes. Don’t worry if dough seems extremely loose and sticky.
5. Add butter, a tablespoon at a time, beating on medium speed until each addition is well incorporated. Add remaining flour gradually, as needed. Give it some time for the dough to come together. Increase speed to high and mix until dough is cohesive and smooth.
6. Lightly grease a large bowl with oil or butter and scrape dough into prepared bowl (it will be very sticky). Cover with plastic wrap. Let rise in a warm spot until about doubled in volume (about one and a half hours).
7. Lift the dough and toss it over on itself a few times to “rompre” the dough (let out the air). Cover the bowl and refrigerate overnight, or up to 24-30 hours.
This dough can be made by hand, but it requires a bit more effort to incorporate all that butter.
* The quarter-size dough yields enough for one large wreath challah, or 12 rosette rolls, or 3 epi breads.