Lightly spray an 8x8 baking dish with non-stick cooking spray and set aside. 

Add the sugar and milk to a medium pan and stir to combine. 

Turn the heat on to medium-low and slowly bring to a boil. 

Continue to boil for 2 ½ minutes, stirring continuously to prevent it from sticking. 

Remove from the heat and stir in the infused peanut butter and the vanilla extract until everything is smooth. 

Pour into the prepared baking dish and allow it to cool completely at room temperature.