Serves: Makes 36 (3 by 1-inch) bars
- 1¾ cups (8¾ ounces) unbleached all-purpose flour
- 1¾ cups (6 ounces) old-fashioned or quick oats (not instant)
- 1 cup (8 ounces) firmly packed light brown sugar
- ¼ teaspoon salt
- 2 sticks (8 ounces) cold unsalted butter, cut into ½-inch pieces
- 1 16 ounce jar good quality seedless raspberry jam
- 1 cup (5½ ounces) dried sour cherries
- Confectioners' sugar, for dusting
Preheat the oven to 350°F and position an oven rack in the center. Line a 13-inch baking pan with foil across the bottom and up the two long sides, then lightly coat with melted butter, oil, or high-heat canola-oil spray.
Mix the crumble dough: Place the flour, oats, brown sugar, and salt in the bowl of the stand mixer and beat on low speed until evenly mixed (or place in the food processor and process for 5 seconds). Add the cold butter and mix on low speed until the mixture looks like wet sand and starts to form clumps, 5 to 6 minutes (or process for 45 to 60 seconds, pausing to scrape down once with the spatula).
Bake the bottom crust: Divide the dough in half. Pat one half into an even layer in the prepared pan. Set the other half aside. Bake for 20 to 25 minutes, until golden and crisp. Transfer to a rack and cool for 20 minutes. Leave the oven on.
Make the filling: Empty the jar of jam into a medium bowl and stir well to break up any lumps. Add the cherries and stir until well mixed and all the cherries are coated with jam. Spread evenly over the cooled crust, all the way to the edges. Sprinkle the remaining dough evenly over the filling.
Bake for 35 to 40 minutes, until the topping is golden brown and the filling is bubbling. Transfer to a rack and cool completely, 1½ to 2 hours.
Un-mold the cookies: To serve, run a thin knife or spatula around the edges of the pan to loosen any dough or filling. Lift the cookies out using the foil as handles and place on a cutting surface. Cut into 3 by 1-inch bars. Just before serving, use the finemesh strainer to lightly dust confectioners' sugar over the cookies.
Storing: Keep the bars in an airtight container between layers of parchment or waxed paper for up to 4 days at room temperature. Dust with confectioners' sugar just before serving.