Peanut Butter Frosted Brownie Bites

I taught Relief Society Meeting in the fall of 2011. My favorite part of the meeting were the yummy brownie bites frosted with a peanut butter cream cheese frosting. I couldn't get enough so I made up my own version!

Brownies:
You can use a mix or my new favorite homemade recipe I found on Pinterest came from Cook Like Your Grandmother.com . I baked these little goodies using a Mini Muffin Pan. If you are using the homemade version you will get approximately 3 1/2 dozen brownies. NOTE: when baking using the mini muffin tins decrease the baking time to 15-17 minutes. Once brownies have cooled frost using the recipe below.
Frosting Recipe:
1/2 c. butter (1 cube)
8 oz cream cheese
1 c. creamy peanut butter
4 c. powdered sugar
1-4 TBS milk
Combine all ingredients with mixer.  Leftover frosting can be frozen for later. I used a Wilton 14 Inch Piping Bagwith a Size 14 Decorating Tip.