Place 3 cups of the flour, sugar, salt, and yeast into the bowl of a stand mixer.In a microwave-safe cup or in a saucepan, melt the butter and milk together until mixture is very hot.
Let it cool down to about 130 degrees (measure with a thermometer for accuracy).Stir in the milk into the flour mixture, then add the egg and vanilla and stir until mixed.
Add remaining cup of flour by quarter cupfuls until dough is sticky. If you weighted your flour, you’ll probably use it all. If you scooped, you might not.Using dough hook attachment of a stand mixer, knead until dough is smooth and elastic.
Place dough into a greased bowl, cover, and allow it to rise in a warm place until doubled in bulk, about 1 1/2 hours.Punch down dough and turn out onto a floured work surface.
Roll HALF of the dough into an 8×12 inch rectangle.
Brush with melted butter.
Mix together cinnamon and brown sugar, then sprinkle evenly over rectangle.
Roll firmly into a log, pinch the ends closed, and tuck them underneath.
Place in a greased and parchment lined 9×5 or 8×4 inch loaf pan.Repeat with remaining half of dough.
Let rise in a warm place until doubled in bulk,Preheat oven to 350 degrees F (175 degrees C).
Brush the top of the loaf with melted butter, then bake in preheated oven until golden brown, and sound hollow when tapped, about 30 minutes.
