Step 1

Preheat oven to 350°F and line a cookie sheet with parchment paper or silicone baking mat. Pour 1/2 cup of sugar into a small bowl and set aside.

Step 2

Whisk together flour, baking soda, and salt in a mixing bowl and set aside.

Step 3

Using a standing mixer or electric hand mixer, cream together butter, brown sugar and peanut butter.

Step 4

Add the egg and vanilla and continue mixing.

Step 5

Gradually pour bowl of dry ingredients into the wet ingredients and mix just until combined.

Step 6

Divide dough into small balls, about 1 inch in diameter each.

Step 7

Form each ball into a log shape, then roll in sugar.

Step 8

Place logs on cookie sheet about 2 inches apart.

Step 9

Using the tines of a fork, make a criss-cross pattern in your dough logs, then pinch the middle of the cookie to make a peanut shape.

Step 10

Bake 10-12 minutes, until lightly browned on the edges, but still soft in center.

Step 11

Allow cookies to cool on baking sheet for 5 minutes before removing to a wire rack to cool completely.

Step 12

Using a standing mixer, beat butter on medium speed until fluffy.

Step 13

Mix in peanut butter, 1 cup powdered sugar, milk and vanilla extract.

Step 14

Gradually mix in the remaining powdered sugar until smooth.

Step 15

Group your baked cookies into pairs, then spoon 1 Tablespoon of filling on the bottom cookie for each pair.

Step 16

Place a second cookie onto the top of the filling to create a sandwich.