01 - Line an 8-inch square baking pan with parchment paper, leaving overhang for easy removal.
02 - In a medium saucepan over low heat, combine chocolate chips, sweetened condensed milk, and butter. Stir constantly until melted and smooth.
03 - Remove from heat. Stir in vanilla extract, dried cherries, and walnuts if using, until evenly dispersed.
04 - Pour mixture into prepared pan and smooth the top with a spatula.
05 - Refrigerate for at least 2 hours or until fully set.
06 - Lift fudge from pan using parchment overhang. Cut into 24 squares and serve chilled or at room temperature.