Preheat your oven to 350°F (175°C). In a large mixing bowl, prepare the Butter Pecan cake mix according to package instructions, incorporating oil, eggs, and water. Pour the batter into a greased 9x13-inch baking pan. Bake for 25-30 minutes or until golden brown. Allow to cool completely.

Once the cake has cooled, poke holes all over the surface approximately 1 inch apart with a skewer. Set aside.

In a saucepan over medium heat, combine brown sugar, unsalted butter, and heavy cream. Stir continuously until it comes to a gentle boil, then simmer for 3-5 minutes until thickened. Remove from heat and add vanilla extract.

Pour the warm praline sauce over the poked cake, spreading it evenly to soak into the holes. Let absorb for about 10-15 minutes.

In a mixing bowl, add heavy cream and powdered sugar. Whip on medium-high until stiff peaks form, about 3-5 minutes.

Spread whipped cream over the cake. Optional: sprinkle toasted pecans on top.

Cover and refrigerate for at least 2 hours before serving.