Add the eggs (in the photo, only one because I did half for testing) and milk.
Mix without insisting then add the bananas and peanut butter.
Mix by mashing the bananas with a fork and incorporating the peanut butter well. Pour in the melted butter.
Pour half of the batter into the 21X21 square pan lined with parchment paper.
Add the milk chocolate chips.
Then cover with the second half of the dough.