Preheat oven to 350°. Line an 8-inch square baking pan with parchment paper, letting excess extend over sides of pan. Spray parchment with baking spray with flour.
In a medium bowl, whisk together flour, oats, brown sugar, baking soda, ¼ teaspoon cinnamon, and salt. Add melted butter, stirring until combined. Reserve ¾ cup crumb mixture. Firmly press remaining crumb mixture into bottom of prepared pan.
In a large saucepan, bring granulated sugar, apple cider, cornstarch, nutmeg, and remaining ¼ teaspoon cinnamon to a boil over medium heat, whisking constantly. Cook until mixture thickens, 2 to 3 minutes. Remove from heat; stir in apple, pear, and vanilla. Spoon mixture over prepared crust. Sprinkle with reserved ¾ cup crumb mixture.
Bake until golden brown and set, 45 to 55 minutes. Let cool on a wire rack for 1 hour. Refrigerate for 4 hours or overnight. Just before serving, garnish with confectioners’ sugar, if desired. Cut into before serving.
Recipe by Southern Lady Magazine at https://southernladymagazine.com/apple-pear-cobbler-bars/