Ingredients

• 2 1/4 teaspoons active dry yeast (a 1/4-ounce package)
• 7 tablespoons warm water (105-115°F)
• 1 2/3 cups unbleached all-purpose flour, divided
• 3/4 teaspoon salt
• 1 large egg, lightly beaten
• 1/4 pound Havarti cheese, coarsely grated
• 1/4 pound salted mozzarella, coarsely grated
• 1 teaspoon unsalted butter, melted
• a floured pizza pan (at least 12 inches) or a floured large baking sheet

Instructions

1. Sprinkle yeast over warm water and stir in 1 tablespoon flour. Let stand until creamy, about 5 minutes. (If yeast does not activate, start over with new yeast.)
2. Stir together salt and remaining flour in a large bowl, then stir in egg and yeast mixture to form a dough.
3. Turn out dough onto a well-floured surface and turn to coat with flour, then knead until smooth and elastic, about 5 minutes. Form into a ball and dust with flour. Let dough rest in a bowl, covered with plastic wrap, punching down with a wet fist every hour, at least 2 hours and up to 3.
4. Preheat oven to 500°F with rack in middle.
5. Turn out dough onto floured pizza pan, turning to coat, then flatten with your fingers into a 7-inch disk.
6. Toss together cheeses and press into a compact 3-inch ball with your hands. Place ball in middle of dough, then gather dough up around ball of cheese, squeezing excess dough into a topknot. Press down on topknot with a damp fist to press cheese out from center. Continue to flatten dough and distribute cheese evenly, pressing outward from center, until dough is an 11-inch disk.
7. Cut a 6-inch X through top of dough to expose cheese. Bake until pale golden, 10 to 12 minutes. Brush surface of dough with butter and bake until golden and cooked through, 3 to 5 minutes more.
8. Serve cut into wedges.