Pumpkin and Fennel Pastries

Name: Pumpkin and Fennel Pastries
Ingredients: 1 fennel bulb (sometimes called anise); About 2 1/3 cups olive oil plus additional for brushing; 1 medium onion, chopped; 1 small pumpkin or winter squash (1 pound), peeled and cut into 1/4-inch dice; 1/3 cup coarse (#3) bulgur; 1/2 teaspoon dried Aleppo chile flakes or other dried hot red pepper flakes, or ground black pepper; 1/2 cup chopped fresh mint; 1 1/2 cups crumbled feta (8 ounces); 1/2 cup grated myzíthra cheese or ricotta salata; 25 (8-inch) squares spring-roll pastry sheets, thawed if frozen; About 2 cups safflower oil; 1 large egg white, lightly beaten