Preheat oven to 350 degrees
Line square glass baking dish with parchment & give a light spritz with cooking spray
In large bowl combine flour, cocoa, baking soda & salt - whisk to combine
In a smaller bowl combine chocolate chips & butter - microwave in 30 second intervals until melted - allow to cool slightly
Add in sugar to melted butter & chocolate- stir
Add eggs, milk & vanilla. - Stir well until combined
Pour into dry mixture & fold until completely combined
Transfer to prepared dish
Bake for 20-30 minutes- might not appear done in the middle - that's okay, they will settle as they cool- that's what keeps it fudgy.
Remove from oven
Cool completely before adding frosting & cutting
Once cool - spread frosting on in an even layer - move on to assembling trifle
*Frosting
In a mixer with a paddle attachment cream butter until light & fluffy
Add in confectioners sugar & beat slowly
Once mixture looks moist but crumbly add in milk & beat until fluffy again - if you want it a little softer add additional milk 1-2 tsp at a time
*Assemble
Cut frosted brownies into bite size pieces & add several pieces into the bottom of your glasses
Sprinkle in your peanut butter morsels
Top with whipped topping & continue in the same process until your glass is full ending with the peanut butter morsels
Refrigerate until ready to serve