Preheat oven to 350°. Spray a 13x9-inch baking dish with cooking spray.
In a medium bowl, stir together flour, oats, cashews, 1 cup sugar, and baking soda. Add melted butter, stirring until well combined. Reserve 1½ cups mixture for topping. Using the bottom of a measuring cup, press remaining mixture into bottom of prepared dish.
Bake for 15 minutes. Let cool completely on a wire rack.
In a medium bowl, beat cream cheese and remaining ¾ cup sugar with a mixer at medium speed until creamy. Add eggs, one at a time, beating well after each addition. Add lemon juice and vanilla, beating to combine.
Spread apple butter onto prepared crust. Spread cream cheese mixture over apple butter. Sprinkle with reserved 1½ cups oat mixture.
Bake until cream cheese layer is set, 35 to 40 minutes. Let cool completely.
Recipe by Taste of the South at https://tasteofthesouthmagazine.com/cream-cheese-oat-bars/