Preheat oven to 350 degrees F. Line a 13x9" baking pan with foil, extending the sides of the foil over the edges of the pan. Spray the foil with cooking spray and set aside.

To make the blondies: In a medium/large sauce pot, melt the butter over medium-low heat. Stir in the brown sugar until combined. Let cool for about 5-10 minutes. After it's cooled off a little, whisk in the eggs and the vanilla until combined. Lastly, whisk in the salt, baking powder and flour until a soft batter forms.

Pour the batter into the prepared pan and spread into an even layer. Bake for approx. 19-22 minutes or until a toothpick inserted near the center comes out clean. Cool completely.

Wipe out the sauce pot and return it to the stove. To make the praline icing: Add the butter and brown sugar to the sauce pot and bring to a boil over medium heat. Stir constantly for 2 minutes. Add in the heavy cream and bring back up to a boil. Immediately remove from the heat and cool slightly, about 10-15 minutes. Once cooled off a little bit, add in the powdered sugar. Fold in the pecans.

Working quickly, spread the praline icing over the blondie base in an even layer. Refrigerate for at least 2 hours to set the icing before cutting into bars.