1-1/4 cups granulated sugar
1/2 cup firmly packed light brown sugar
1-1/2 Tablespoons cornstarch
4 cups pitted, tart, fresh or frozen, thawed cherries
1/3 cup water
2 teaspoons grated lemon or orange zest
1/2 teaspoon vanilla or almond extract
1/4 teaspoon ground allspice
1/8 teaspoon ground cinnamon
8 sheets phyllo pastry, thawed if frozen
3 Tablespoons butter, melted
1 Tablespoon confectioner's sugar
To prepare filling, in a medium saucepan, mix together granulated sugar, brown sugar, and cornstarch. Stir in cherries, water, lemon zest, and vanilla. Cook over medium heat until bubbling and thickened. Reduce heat to low, add allspice and cinnamon, and cook, stirring occasionally, for 15 minutes. Remove pan from heat. Cool completely.
Preheat oven to 400º. Grease a baking sheet. To prepare pastry, unfold sheets of phyllo so they lie flat. Stack 4 sheets on plastic wrap. Brush top sheet with one tablespoon melted butter. Keep remaining sheets covered with plastic wrap and a damp cloth to prevent them from drying out.
Spread half filling along a short side of top pastry sheet. Starting with short side and using plastic wrap as a guide, roll up pastry, jelly-roll style. Fold ends under. Place strudel, seam-side down, on prepared baking sheet. Brush with 1/2 tablespoon melted butter. Repeat with remaining phyllo, melted butter, and filling to make second strudel.
Bake until golden, 15-20 minutes. Transfer baking sheet to a wire rack to cool for 15 minutes. Transfer strudels to a cutting board to cool completely. Sprinkle with confectioner's sugar. To serve, cut strudel diagonally.