Preheat oven to 350°. Spray a 13x9-inch baking dish with baking spray with flour.
In a large bowl, stir together flour, granulated sugar, pecans, powdered milk, baking powder, salt, baking soda, and nutmeg. Add 1 egg and ¾ cup melted butter; beat with a mixer at medium speed until combined. (Mixture will be crumbly.) Press mixture into prepared pan.
In a large bowl, beat cream cheese, vanilla, remaining 2 eggs, and remaining 1 cup melted butter with a mixer at medium speed until combined. Add confectioners’ sugar, beating until smooth. Spread over crust mixture.
Bake until golden brown and center jiggles slightly, 45 to 50 minutes. Let cool completely. Cut into squares. Serve with Butter Pecan Sauce, if desired.
Recipe by Taste of the South at https://tasteofthesouthmagazine.com/ooey-gooey-butter-pecan-cake/