1. Adjust oven rack to lower-middle position; heat oven to 475°F. Combine raisins and Poire William in small microwave-safe bowl; cover tightly with plastic wrap and microwave on high until simmering, about 1 minute. Let stand, covered, until needed.

2. Melt 1 tablespoon butter in small skillet over medium heat; when foaming subsides, add bread crumbs and cook, stirring frequently, until golden brown, about 2 minutes. Transfer bread crumbs to small bowl and set aside.

3. Peel, quarter, and core pears; cut each quarter lengthwise into 1/8-inch-thick slices. Drain off and discard any remaining liquid from raisins. Toss pears, raisins, bread crumbs, 1/4 cup granulated sugar, walnuts (if using), cinnamon, salt, and lemon juice in large bowl to combine. Divide filling into two equal portions.

4. Melt remaining 6 tablespoons of butter. Place sheet of parchment paper slightly larger than phyllo on work surface, long side toward you. Place one phyllo sheet on parchment and brush with butter then sprinkle with 1 teaspoon sugar. Repeat with four more sheets. Place filling in 3-inch-wide strip about 1 1/2 inches from bottom and 2 inches from sides of phyllo. Fold short ends of phyllo over pears. Fold end closest to you over pears. Roll loosely, using parchment as guide. Dont roll too tight, as this can cause tearing during baking. Place strudel, seam side down, on baking sheet. Brush with butter and sprinkle with remaining sugar. Repeat with remaining five sheets of phyllo and filling to make second strudel. Cut three 1-inch vents into top of each strudel for steam to escape. Bake until golden brown, 15 minutes. Cool on baking sheet on wire rack until warm, about 40 minutes.

5. Place confectioners sugar in metal strainer and dust strudels. Using 2 large metal spatulas, transfer strudels to platter or cutting board, cut into slices with serrated knife, and serve with topping, if desired.

Makes two strudels, serves 6 to 8