The Easiest Apple Strudel

Name: The Easiest Apple Strudel
Ingredients: 1 (1-pound) package frozen phyllo dough (13x18-inch), thawed in the refrigerator overnight; 1/3 cup raisins; 2 tablespoons dark rum or water; 8 tablespoons (1 stick) unsalted butter; 1/2 cup panko breadcrumbs; 1 1/2 pounds tart baking apples (about 3 medium), such as Granny Smith or Honeycrisp; 5 tablespoons granulated sugar, divided; 1 tablespoon freshly squeezed lemon juice; 1/2 teaspoon ground cinnamon; 1/4 teaspoon kosher salt; Powdered sugar, for serving; Freshly whipped cream or vanilla ice cream, for serving (optional)