I made outrageous brownies the other night after I made chocolate chip cookies that morning.
https://www.foodnetwork.com/recipes/ina-garten/outrageous-brownies-recipe3-1916679
I would rate them as moderate difficulty only because there are so many little steps. If you lay out all of your ingredients in order before you start, you will be ok.
My other tip is to melt the butter first then the unsweetened chocolate and finally melt the semi sweet chips gradually.
If you have poor air flow in your kitchen, open a window. Between using a double boiler and the oven, I nearly passed out from how hot my galley kitchen
I used a butter and floured 12x16" sheet pan and it made 30 3" brownies. I froze the ones I didn't give away and they now have a more fudge like quality to them which imo, is the best way to eat these.