Preheat the oven to 350℉. Spray a 9x13 baking pan with nonstick spray.
In a large bowl, stir together the peeled and sliced pears, light brown sugar, cornstarch, cinnamon, and nutmeg until the mixture is well combined and all the pears are coated well. Evenly spread the pear mixture out into the baking pan.
3 pounds pears, 1/2 cup packed light brown sugar, 1 tablespoon cornstarch, 1 tablespoon ground cinnamon, ¼ teaspoon ground nutmeg
In a medium bowl, whisk the all-purpose flour, oats, light brown sugar, and baking powder.
1 cup all-purpose flour, 1 cup whole old-fashioned oats, 1/2 cup packed light brown sugar, 1 teaspoon baking powder
Add the cold cubed butter and use your clean hands and fingers to pinch together and mix the butter and flour together until it forms pea-sized pieces. Sprinkle it evenly over top of the pears inside the baking dish.
1/2 cup (1 stick) salted butter
Bake for 45-50 minutes or until golden brown.
Serve the pear crisp warm with a scoop of vanilla bean ice cream, enjoy!