Preparation / Directions:
In small saucepan, heat 1 cup milk just until bubbles appear around the side of pan. Remove from heat; transfer to large bowl and cool to 110-115 degrees. Add 1 cupflour, the yeast and sugar; stir until completely blended. Set aside 20 minutes - mixture will become foamy and rise. Add 3 cups flour, the potatoes, butter and salt to yeast mixture. With wooden spoon, stir until a manageable dough is formed. Turn out onto floured surface and knead dough, adding remaining flour, if necessary, until smooth and elastic, aobut 12-14 minutes. (Dough should be moist but not sticky.)
Wash, dry and oil mixing bowl. Place dough in oiled bowl, turning to bring oiled side up. Cover with clean cloth; let dough rise in warm place until double in size, about 1 hour. On floured surface, roll dough into 18 inch round. Unravel string cheese and pull thick strands apart to create thinner strand. (If using mozzarella, cut into 1/4 inch cubes.) Combine cheese with thyme and rosemary; mound cheese and herb mixture in center of dough round, leaving about a 6 inch border of dough. Gently pull up edge of dough and bring to center, allowing dough to fold in a spiral fashion, covering cheese and
herb. Pinch ends of dough at center to close bread and create a "topknot". Transfer bread to large, greased baking sheet. Cover with clean cloth and let rise 45 minutes. Heat oven to 350*. In small bowl, beat together egg and remaining 1 tbsp of milk. Brush top of bread with egg mixture and sprinkle with poppy seeds. Bake 55-60 minutes, or until golden brown and center is firm. Cool bread 20 minutes on wire rack before cutting. Serve warm. *This reheats well; just wrap in tin foil and heat in oven for 10-20 minutes.