I made these two recipes for a church potluck and I didn't video the process but don't worry, I will walk you through it!
I have been making these for YEARS and I think you will love how easy they are.
Start with your favorite brownie mix! I use the box of Hershey Brownie Mix from Sam's club* because it turns out so perfectly every time.
The trick to doing the marshmallow layer is to take the brownies out about 3 minutes before they are done and cover them with mini marshmallows. Put them back in the oven and let them cook until the marshmallows are puffed and golden on top. The progression will look like this:

(Pretend those marshmallows are on top of your brownies ;) )
Once they are COMPLETELY cooled you can top them with your favorite frosting or use this homemade fudge from Sally's Baking Addiction. I used a bar of dark chocolate from Trader Joes in the recipe but you can use milk or semi sweet, whatever you prefer!
I 4x the recipe and had a full mason jar left over so use discretion. Doubling it would have been plenty but we aren't mad about it!
So Good!
For the peanut butter brownies I used the same brownie mix and added some peanut butter cookie dough, this is such EASY dough you wont believe it.
Peanut Butter Cookie dough:
1 Cup creamy peanut butter ( I used this non stir brand)
1 egg
1 cup sugar
1 Tbl vanilla
1/4 cup flour
That's it! just mix it together and drop it over the unbaked brownies and use a knife to blend them in a little.

Hope you love these as much as we do.
And of course stay tuned to see how I made these into Cake Pucks!
*Sam's club links are affiliate :)