Preheat the oven to 350F and line a large baking sheet with parchment paper.
In a medium-sized bowl, whisk together the flour, salt, baking soda, and baking powder and set aside.
Fill a ziplock bag with the original M&Ms and seal shut. Use a rolling pin and wack the M&Ms to roughly crush into smaller pieces. Set aside.
In a mixing bowl using a hand or stand mixer with the paddle attachment, mix together the butter and sugars. Mix on medium-high speed for 2-3 minutes or until light and fluffy.
Scrape down the bowl and mix in the eggs one at a time on medium-high speed. Once combined, scrape down the bowl and mix for another good 2-3 minutes, followed by the vanilla.
Scrape down the bowl again and mix in half of the dry ingredients on low-medium speed. Once almost combined, mix in the rest of the dry ingredients again on low-medium speed. Careful not to over mix.
Pour in the crushed and mini M&Ms and use a rubber spatula to gently fold into the dough. Again, careful not to over mix.
Using a large 2 oz cookie scoop, or ¼ measuring cup, scoop the dough out onto the baking sheet. Only bake about 4-5 cookies at a time and space them well apart as they spread quite a bit.
Top with more M&Ms, and bake for 12-15 minutes. They’re ready when the edges are lightly golden and the center is pale, puffed, and slightly underdone. Right when they’re pulled from the oven, use a fork to nudge in around sides of the cookies.
Sprinkle the cookies with even more M&Ms and a pinch of sea salt (both optional but recommended).
Transfer to a cooling rack and allow the cookies to cool for about 15 minutes. Then dig in!
