Boil the Base: In a medium saucepan, combine sugar and milk. Bring to a boil over medium heat, stirring often. Boil for about 3 minutes, or until the sugar completely dissolves.
Mix in Flavor: Remove from heat and stir in peanut butter and vanilla extract until smooth and creamy.
Set the Fudge: Pour the mixture into an 8×8-inch pan lined with parchment paper or lightly greased.
Cool and Slice: Let it cool at room temperature, then cut into squares once set.
