Honey Pan Dulce with Nuts and Dried Fruit

Place 1/2 cup warm milk and 1 teaspoon sugar in large bowl; sprinkle yeast over and stir to blend. Let stand until yeast dissolves and mixture looks foamy, about 5 minutes. Mix in 1/2 cup flour to form soft sponge. Cover sponge and let stand until very light and bubbly, about 30 minutes. Whisk eggs, honey, butter, lemon and orange peel, salt, remaining 1/4 cup milk, and 6 tablespoons sugar in medium bowl to blend. Stir egg mixture into sponge. Mix in 3 cups flour, 1 cup at a time, to form soft dough. Mix in additional flour, 1 tablespoon at a time, until dough is soft and just barely sticky. Turn out onto floured work surface. Knead dough until smooth and elastic, sprinkling with more flour by tablespoonfuls if still sticky, about 8 minutes. Butter another large bowl. Form dough into ball. Place in bowl; turn to coat. Cover bowl with plastic wrap. Let dough rise in warm draft-free area until doubled in volume, about 1 1/2 hours. Gently press dough down. Sprinkle with all fruits and nuts; knead in bowl to distribute evenly. Remove center tube of an angel food cake pan and place an 8-inch-diameter tart pan bottom inside to create 12-cup baking mold. Spray mold with nonstick spray, then butter and flour pan. Form dough into round. Place in prepared pan. Cover with plastic wrap. Let rise in warm draft-free area until almost doubled in volume and almost level with top of pan, about 1 hour 15 minutes. Preheat oven to 375 °F. Bake pan dulce until deep brown on top and tester inserted into center comes out clean, about 45 minutes. Let stand in pan 5 minutes. Turn out onto rack and cool completely. DO AHEAD Can be made 1 day ahead. Wrap in foil and store at room temperature. *Available at some specialty foods stores and candy stores.