- Make sponge by whisking together milk, yeast, 3 eggs, and 3 cups flour. Cover with plastic wrap and let rise until doubled.
- In bowl of stand mixer fitted with dough hook, combine sponge, sugar, salt, 1 cup flour, and squash purée. Add 3 eggs, one by one, mixing well after each addition. Knead until smooth and elastic.
- Add butter, mixing until fully incorporated. Cover and let rise overnight until doubled in size.
- Punch down dough, form into loaf, and place into greased and floured Pullman loaf pan. Cover with plastic and let rise until doubled in size.
- Preheat oven to 350 degrees. Bake loaf about 50 minutes. Let cool on rack, then unmold to cool completely before slicing.
- Whisk together all ingredients. Slice brioche then soak in custard.
- In saucepan over medium heat, melt butter. Whisk in sugar and heavy cream. Cook, whisking constantly, about 5 minutes. Whisk in fleur de sel, vanilla, and rum. Remove from heat and serve warm.
Butternut Squash Ice Cream
- In saucepan set over medium-high heat, bring 4 cups heavy cream to boil. Whisk
together egg yolks and sugar, then temper with hot heavy cream.
- Cook mixture over medium heat until thickened. Whisk in squash purée and strain through fine chinois.
- Stir in salt and remaining cream. Chill thoroughly then process in ice cream maker.
- Heat butter, sugar, water, and salt to soft-ball stage. Add vanilla and pecans, stirring constantly. When crystalized, remove pecans. Cool on a silpat.
- Heat 1–2 tablespoons butter over medium-high heat. Add soaked slices of brioche. Cook on both sides until deep golden brown. Serve hot with warm butterscotch sauce, ice cream, and buttered pecans.