01 - Combine flour, sugar, yeast, and salt in a large mixing bowl. Whisk thoroughly to distribute yeast evenly.
02 - Add warm milk, warm water, melted butter, and egg to dry ingredients. Stir until a shaggy, sticky dough forms.
03 - Knead on a floured surface for 8-10 minutes or use a stand mixer with dough hook for 6-7 minutes until smooth and elastic.
04 - Place dough in a greased bowl, cover with plastic wrap or towel, and let rise in a warm place for 1 hour until doubled in size.
05 - Punch down risen dough and roll out on a lightly floured surface to a 16x12-inch rectangle.
06 - Mix softened butter and Biscoff spread until creamy and well combined.
07 - Spread filling mixture evenly over rolled dough. Sprinkle with brown sugar and cinnamon. Roll up tightly from the long edge and slice into 12 even rolls.
08 - Arrange rolls in a greased 9x13-inch baking dish. Cover and let rise for 45-60 minutes until puffy and nearly doubled.
09 - Preheat oven to 350°F.
10 - Bake for 22-25 minutes until golden brown and cooked through. Centers should be fully baked, not doughy.
11 - Whisk melted Biscoff spread, powdered sugar, and 2 tbsp milk until smooth. Add additional milk if needed to reach drizzling consistency.
12 - Drizzle warm glaze evenly over freshly baked rolls. Serve immediately while warm for optimal texture.