01 - Line an 8-inch square baking pan with parchment paper, leaving overhang to allow easy removal.
02 - In a medium saucepan over low heat, melt chocolate chips, sweetened condensed milk, and 2 tablespoons butter, stirring until smooth. Remove from heat and stir in vanilla extract.
03 - Pour the chocolate mixture into the prepared pan and spread evenly with a spatula.
04 - In a separate bowl, combine creamy peanut butter, powdered sugar, melted butter, sea salt, and vanilla extract. Mix until smooth and creamy.
05 - Gently spread the peanut butter mixture over the chocolate layer, smoothing the surface evenly.
06 - Refrigerate the layered mixture for at least 2 hours until firm.
07 - Lift the set fudge out of the pan using the parchment overhang and cut into 36 uniform squares with a sharp knife.
08 - Store finished pieces in an airtight container in the refrigerator for up to one week.