Mix together all of ingredients for crust and press into a 9-inch square baking dish. Bake for 6 minutes.
In an electric mixer cream together cream cheese, brown sugar, and vanilla until smooth and creamy, about 2 minutes.
Add in flour and mix until well blended.
Beat in eggs one at a time, scraping down sides as necessary.
Gently stir in sour cream until everything is combined.
Pour over baked crust and place in oven for 40-50 minutes until edges are lightly golden brown and center is set. Remove from oven and let cool.
Meanwhile prepare topping by mixing together brown sugar and heavy cream in a small saucepan over medium heat. Bring to a boil, reduce heat and let it simmer for 10 minutes, stirring frequently.
Remove sugar mixture from heat, stir in pecans, and vanilla extract. Pour over bars and spread into an evenly layer.
Place in fridge for a few hours for praline to set before slicing to serve.
Store bars in an air tight container in the fridge.