Preheat oven to 400 degrees.
In a bowl, mix the sausage with the rosemary and pepper. Divide it into 20 pieces, rolling into little balls, then refrigerate them until needed.
In a small bowl, whisk egg and water until frothy. Remove biscuits from packaging and dimple each biscuit’s center using your thumb. Insert sausage balls in centers and place biscuits close together on a lightly greased cookie sheet. Brush exposed biscuit dough with egg wash and top with rosemary sprigs. Bake 12 to 15 minutes, or until biscuits are golden and sausage is thoroughly cooked through. Serve warm.
Food safety note: Use a meat thermometer to check the sausage once the rolls are removed from the oven. For beef and pork sausage, the internal temperature should be at least 160 degrees.