Preheat your oven to 350°F (175°C) and prepare a 9×13-inch cake pan by coating it with non-stick spray.

In a large mixing bowl, prepare the butter pecan cake mix according to the package instructions. Pour the batter into the prepared cake pan and bake for about 30 minutes.

Once the cake is baked, remove it from the oven and let it cool in the pan for about 10 minutes. Poke holes all over the warm cake.

Pour the sweetened condensed milk generously over the holes and let the cake cool completely in the pan.

In a small saucepan, melt the unsalted butter over medium heat. Add the brown sugar and heavy cream, whisking until well combined. Simmer for 3–5 minutes.

Pour half of the warm praline sauce over the cake, focusing on the holes and set the cake aside to cool slightly.

In a mixing bowl, combine the heavy whipping cream, powdered sugar, and vanilla extract. Whip until stiff peaks form.

Spread the whipped cream over the cooled cake, drizzle the remaining praline sauce, and sprinkle toasted pecans on top.

Cover the cake with plastic wrap and refrigerate for at least 2 hours before serving.