Step 1

Heat a medium size sauce pan over medium heat. Melt butter, then add brown sugar. Stir continuously until sugar dissolves and it begins to simmer and a thick brown caramel begins to form. This usually takes 6-8 minutes for me. (see video below)

Step 2

When the sauce is thickened and looks like caramel remove from heat and stir in the peanut butter and vanilla extract (if using) until melted.

Step 3

Line a loaf pan with wax paper and carefully pour the fudge into the pan.

Step 4

Freeze 30 minutes or until completely set.

Step 5

Peel the wax paper away from the fudge and slice. (I slice the loaf into three long skinny rows, then slice the long rows into 7 chunk size pieces.)

Step 6

Top with sea salt as desired.

Step 7

Store in freezer.