Cut 1 stick butter into cubes, add to food processor and bring to room temperature.
Line 8" x 8" baking pan with parchment paper, leaving extra length on ends to ease in removal of Buckeye Shortbread Bars from pan.
Blend butter until creamy consistency.
Add sugar and salt and blend well. Once combined, add flour and blend well.
Press shortbread mixture firmly into parchment lined baking pan and bake for 20 minutes. Allow to cool for at least 20 - 30 minutes
Peanut butter layer
Combine peanut butter, butter, heavy cream and vanilla extract in food processor. Once combined gradually mix in powdered sugar.
Spread peanut butter mixture over shortbread.
Chocolate layer
Add chocolate chips and butter into a microwave safe bowl and microwave in 15 second increments until fully melted, stirring well between each increment.
Spread over peanut butter layer.
Allow to set for at least 30 minutes before cutting.
Notes
I like my peanut butter to chocolate ratio to be 1:1 but if you prefer less chocolate, simply cut the chocolate layer recipe portion in half.