Step 1

Preheat oven to 350 degrees F.

Step 2

Line a 9x13'' pan with parchment paper (or spray with cooking spray.)

Step 3

Place graham cracker sheets along the bottom of the pan.

Step 4

Add butter to a large saucepan over medium heat and allow it to melt. Add the brown sugar and pecans, and stir constantly, bringing the mixture to a full boil.

Step 5

Boil for 5 minutes, stirring constantly.

Step 6

Remove from heat and pour mixture over graham crackers and spread into an even layer.

Step 7

Bake for 7 minutes.

Step 8

While the bars are baking, unwrap the Hershey's chocolate bars and break them into pieces.

Step 9

Remove bars from oven and carefully place chocolate pieces across the top of the toffee layer. Cover the pan with a lid or aluminum foil to allow the chocolate to melt (5-10 minutes).

Step 10

Once chocolate has begun to melt, remove the lid and use a spatula to spread the melted chocolate evenly over the bars.

Step 11

Allow to cool completely before serving. I like to store mine in the fridge to set up (not required) but I leave them out at room temperature for 15 minutes before cutting them, to allow the chocolate to soften.