How to Make It
Prepare the Cake: Preheat oven to 350°F. Beat sugar and butter in a stand mixer fitted with a paddle attachment on medium speed until light and fluffy, about 3 minutes. Add egg, beating well. Stir together flour, baking powder, and salt in a separate bowl; add to sugar mixture alternately with milk, beginning and ending with flour mixture, beating on low speed until just combined after each addition. Stir in vanilla.
Pour batter into a heavily greased 8-inch round or square cake pan. Bake in preheated oven until a wooden pick interested in center comes out clean, 23 to 28 minutes. Transfer to a wire rack. (Do not turn oven off.)
Prepare the Praline Glaze: Stir together brown sugar, butter, milk, and flour in a bowl until well combined. Stir in pecans.
Spread Praline Glaze over hot Cake. Bake at 350°F for 5 minutes. Transfer to a wire rack; let cool completely, about 1 hour.