Preheat oven to 325 degrees F. Line 2 baking pans with parchment paper.
Add the first three ingredients into a bowl. Set aside.
In a microwave-safe bowl, add in the semi-sweet chocolate chips and butter. Place into the microwave and heat for 30 seconds. Stir thoroughly.
Microwave for another 20 seconds and stir thoroughly.
If the chips aren't completely melted, microwave one more time for 20 seconds and stir again. Set aside and immediately start working on the next step.
In a large mixing bowl, add in the granulated and brown sugar, 3 eggs, and vanilla extract. Beat for about 1 - 2 minutes on high until thick and pale.
Immediately add in the warm semi-sweet melted chocolate, dry ingredients, and 1 cup of m&m's. Beat until everything is incorporated. Use a spatula and scrape the bottom to get all of the chocolate incorporated.
Using a large scoop, scoop out all of the batter onto the prepared pans. I did 6 - 7 scoops per a pan. Leave a little room for the cookies to spread.
If you have extra batter, pull out some extra parchment paper that will fit on the baking pan and scoop the remaining onto that paper. It's important to get all of the dough scooped and ready for the oven before the chocolate cools and gets rough. You won't get the shiny crinkled brownie top if it gets to the rough texture.
Sprinkle a handful of extra m&m's on top of the cookies for extra color.
Place into the oven and bake for 17 minutes. This will depend on the size of the cookies. Mine were HUGE! Remove from the oven and let cool for about 15 minutes before moving them. This will help them pull away from the parchment paper and stay together while moving them.