Defrost dough according to directions on package. Roll dough into a rectangle that is 14" long and as wide as your bread pan (usually 8"–9"). With the short side of the rectangle facing you, spread pesto evenly on dough leaving a 1" border all the way around.

Cut the mozzarella cheese block into finger-shaped pieces then line the pieces down the center of the dough over the pesto. Roll dough tightly into a cylinder. Pinch the seam and sides together to seal in the pesto and cheese. Coat bread pan with non-stick spray then place dough seam side down into pan. Cover with a clean kitchen towel then let it rise for about 1–1½ hours until doubled in size.

Preheat oven to 350 degrees then bake bread 40–45 minutes or until top is golden brown and the bread is cooked through. Remove from oven then brush with butter. Let bread cool for 5 minutes before removing from the pan. Transfer to cooling rack for 10–15 more minutes, then slice and serve nice and warm. Enjoy!