Preheat your oven to 180 C (350 F), get out a 9x13 baking dish and grease it with butter or cooking spray.

In a mixing bowl, whisk together the flour, baking soda, and salt.

In a large mixing bowl, mix together the butter and brown and white sugars with an electric mixer until light and fluffy.

Add the eggs one at a time while beating the mixture, then beat in the peanut butter, sour cream, and vanilla.

Beat in half the dry ingredients from the other mixing bowl, beat until just mixed in.

Add the milk and beat until fully mixed. Add the remaining dry ingredients and beat until just mixed together.

Pour the batter into the prepared baking dish and spread out evenly. Bake for 35 minutes or until a toothpick inserted in the center comes out clean.

Remove from the oven and place on a rack to cool completely.

When the cake is completely cooled, add the cream cheese and butter to a large mixing bowl and beat with an electric mixer until there is no more lumps.

Add the peanut butter.

Beat in the peanut butter until fluffy.

Add the powdered sugar, vanilla, and salt and mix until combined. Add the cream and mix in until well combined.

Frost the cake.

Melt the peanut butter (I used the microwave for 15 seconds, stirred, then another 15 minutes, perfect). Measure out the chopped Reese's (I used 10 mini Reese's and chopped those) and mini chocolate chips.

Drizzle the cake with the melted peanut butter.

Sprinkle with the Reese's and chocolate chips.

Cut into squares, serve and enjoy.