No-Knead Buttermilk Pull-Apart Rolls

Name: No-Knead Buttermilk Pull-Apart Rolls
Prep time: 3 h
Cook time: 25 min
Total time: 3 h 25 min
Cuisine: American
Ingredients: 4.25 cups (550 g) all-purpose or bread flour, plus more for shaping; 4 to 5 teaspoons kosher salt (12 to 15 g), see notes above; 2 tablespoons (25 g) sugar; 2 teaspoons (8 g) instant yeast; 1 scant cup (235 g) boiling water, or less, see notes above; 1 scant cup (235 g) buttermilk; 6 tablespoons melted butter, divided; flaky sea salt