Preheat the oven to 350ºF. Spray an 8x8" baking pan with cooking spray, or line it with parchment paper. Using parchment paper will allow you to easily remove the bars from the pan and cut them evenly.
In a medium size bowl, mix together the flour, sugar and melted butter. Press this mixture into the bottom of the prepared pan. Bake for 20 minutes.
In the same bowl, mix together the toffee bits, sweetened condensed milk, vanilla and chopped pecans. Pour this mixture onto the crust. Bake for another 20 minutes until the top is bubbling.
In a microwave safe bowl, melt the chocolate chips in 15 second intervals, stirring between each interval, until the chocolate is melted.
Drizzle the chocolate over top the baked bars.
Allow the bars to cool completely, then cut them into squares.
Store in an airtight container at room temperature for up to 3 days. Then refrigerate or freeze.
You can make this in a 13x9 inch pan if you'd like to get more bars. The two layers will just not be as thick. The baking time may need to be reduced just a bit if you choose this option.Refer to the article above for more tips and tricks.The calories shown are based on the bars being cut into 16 pieces, with 1 serving being 1 bar. Since different brands of ingredients have different nutritional information, the calories shown are just an estimate. **We are not dietitians and recommend you seek a nutritionist for exact nutritional information. The information in the nutrition box are calculated through a program and there is room for error. If you need an accurate count, I recommend running the ingredients through your favorite nutrition calculator.**