Preheat your oven to 350°F (175°C). Coat a 9x13-inch cake pan with non-stick spray.

In a large mixing bowl, combine the butter pecan cake mix according to the package instructions. Mix until smooth, about 2 minutes. Pour into the prepared pan and bake for approximately 30 minutes.

Remove from the oven and cool for about 10 minutes. Poke holes all over the top with a fork or wooden spoon handle.

Pour the sweetened condensed milk over the warm cake, allowing it to seep into the holes. Let sit for about 30 minutes.

In a medium saucepan over medium heat, melt the unsalted butter. Stir in brown sugar and heavy cream. Simmer for 3-5 minutes until thick.

Remove from heat and let the praline sauce cool slightly. Drizzle half over the cooled cake.

In a medium bowl, whip heavy whipping cream, powdered sugar, and vanilla extract until stiff peaks form.

Spread the whipped cream over the cake. Drizzle remaining praline sauce and sprinkle with toasted pecans.

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