Dark chocolate peanut butter fudge

Directions

1. Over medium heat, melt the butter in a large saucepan.
2. With a wooden spoon, stir in the brown sugar and milk, removing any lumps, and bring to a boil for 2 to 3 minutes without stirring.
3. Remove from the heat, and stir in the vanilla, then the peanut butter.
4. Add powdered sugar, and beat with a wooden spoon until smooth.
5. Pour into an 8-inch square baking pan, cover the top with parchment, and press down to smooth out the top. Set aside to cool slightly, about 10 minutes. Place in the fridge to cool completely.
6. Turn the fudge out of the tin onto the parchment. Melt the chocolate, pour it over the fudge, and use an offset spatula to smooth the top. Allow the chocolate to set, and sprinkle flaky sea salt over.
7. Cut into 36 squares and serve.