In brief
King Arthur Baking's Vanilla Cream-Filled Brioche uses buttery yeasted dough developed by kneading and a separate vanilla cream. Baked brioches are split for filling.
Useful to know
King Arthur Baking's Vanilla Cream-Filled Brioche uses buttery yeasted dough developed by kneading and a separate vanilla cream. Baked brioches are split for filling. [1]
Initial stickiness does not automatically mean incorrect proportions. The recipe notes that development takes time. Distinguish dough handling from preparing and storing the filling.
Sources
For further detail and to check the information: