Preheat the oven to 350°F. Line an 8 by 8-inch pan with foil or parchment. Spray with nonstick cooking spray. Don't skip this, the caramel filling gets sticky!
In a large bowl combine the butter and sugar with a rubber spatula. Add the eggs, egg yolk, molasses, and vanilla and stir until combined. Stir in the salt and flour.
Pour half the batter into the prepared pan. Bake for 15 minutes, or until the top begins to set. Keep oven at 350°F.
Meanwhile, combine the unwrapped candies with the cream in a microwave safe bowl. Microwave in 30 second bursts, stirring between bursts, until the mixture is melted and smooth. Stir in the pecans.
Pour the caramel over the middle of the bottom baked blondie layer. Pour the remaining batter over the caramel layer is completely covered.
Return to the 350°F oven and bake for another 30 minutes, or until golden brown and set. Let cool completely before chopping into bars with a big sharp knife. Wipe the blade with hot water for cleaner slices.
Serve or store in an airtight container at room temperature for up to 3 days.