Preheat the oven to 375 degrees. Spray 1 1-quart 8x8" baking dish or oven-proof skillet with vegetable spray and set aside.
MAKE THE CRUMBLE TOPPING:
Place ⅓ cup + 2 tablespoons all purpose flour, 3 tablespoons granulated sugarr, ¼ teaspoon kosher salt, ¼ teaspoon ground ginger and 5 tablespoons cold, unsalted butter into the bowl of a food processor and pulse until mixture resembles coarse meal.
Transfer to a bowl and with your fingers, work the mixture, squeezing to create a lumpy, crumbly texture.
Add ¾ cup sliced almonds and toss to combine. Refrigerate until ready to top the crumble.
FOR THE PEAR FILLING:
Peel 5 firm, ripe pears and halve them with a sharp knife. Cut the halves in half again and remove the core using a melon baller or teaspoon. Cut out the tough stem. Chop the pears into ¾-1" bite-sized pieces.
Transfer pears to a large bowl and sprinkle with 2 tablespoons lemon juice. Toss to coat. Add ⅓ cup granulated sugar, 2 tablespoons crystallized ginger, ½ teaspoon cinnamon and ¼ teaspoon ground nutmeg.
In a small bowl, mix 1 tablespoon water and 1 teaspoon cornstarch together to form a slurry. Pour over the pears and toss to coat the pears with the slurry and spices. Transfer the pears to the prepared baking dish.
BAKING THE PEAR CRUMBLE:
Liberally sprinkle the almond topping over the pear filling. Bake for 50 minutes to 1 hour until the fruit is tender, but not mushy and the topping is a warm, golden color.
If the fruit is tender, but the topping is pale, place it under the broiler for 4-5 minutes to get a little color. Serve warm with a scoop of vanilla or a drizzle of cream.
Notes
You can assemble the dessert up to one day before (store it covered in the refrigerator) and bake it the next day.
It may need additional baking time (10 minutes or so) if it's coming straight from the fridge to the oven.
Cover and refrigerate leftover pear crumble for up to 2-3 days.
You can reheat the crumble recipe in a warm (325°) oven for 10-15 minutes or in the microwave in 20-30-second bursts.
For a crisp topping, it's better to reheat the warm pear dessert in the oven.
To freeze a baked crumble, place it in an airtight container for up to 2-3 months.
For unbaked crumble, cover it tightly with plastic wrap and foil, then freeze for up to 3 months.
The unbaked version can be cooked directly from frozen, but it will take longer to bake than the original pear crisp recipe calls for.
Baked and frozen crumble should be thawed in the refrigerator overnight before reheating.