Step 1

Preheat oven to 350 degrees Fahrenheit.

Step 2

In a large bowl, blend together the peanut butter and butter.

Step 3

Beat in brown sugar, eggs and vanilla.

Step 4

Add flour and salt.

Step 5

Spread into a greased 13×9 inch baking pan.

Step 6

Bake for 30-35 minutes.

Step 7

Cool in pan and frost.

Step 8

Sprinkle Reese’s Pieces on top of brownies.

Step 9

Blend peanut butter and margarine until fluffy.

Step 10

Blend in remaining ingredients until smooth.

Step 11

Frost cooled brownies.