You just need the usual cooking suspects. I'll buy the generic brand of almost every ingredient I need, including spices (which some would say is very bad, for lack of a better word). But I draw the line at vanilla. Buy the good stuff. I like Red Rooster Mexican vanilla (pictured), available at any fine grocer's establishment.
You'll need three bowls for this recipe. Yes, it's a pain. But it's true. Although I suppose you could cheat and not mix the flour in the small bowl...
In your largest bowl, put 1/2 c. white sugar, two room-temperature eggs, and 1 tsp. vanilla.
Using your hand mixer, beat on high until thickened and fluffy, about five minutes. You won't believe the transformation. And you'll be so glad you don't have to do it by hand.
Then, put your 2 1/2 cups milk chocolate chips in a bowl with 2 Tbsp. room-temperature butter. Microwave until partly melted.
Stir gently to finish melting it all together. Delicious if you want to taste just a tiny bit...
Put your chocolate mixture into your egg/sugar mixture.
Mix on medium until well blended.
Then add (theoretically, you would first put the following ingredients in their own small bowl and whisk them together!) 1/4 cup plus 2 Tbsp. flour, 1 tsp. baking powder and 1/2 teaspoon salt.
Mix until well blended; stick the batter in the fridge so it's easy to scoop onto your baking sheets.
Line 2 baking sheets with parchment paper (important! don't skip the parchment paper! it will keep the cookies from sticking!) and drop dough onto sheets - 12 drops per sheet.
It's a thick batter, almost fudgy. And delicious, too, though it's not recommended you eat it because it has raw eggs.
Bake at 350 for 15 minutes, turning baking sheet halfway through cooking time. When mine were done, I gently lifted the parchment paper from the baking sheet, and then started removing the cookies.
Yummmmm... but I can't eat any because then I won't have enough for the fam.... Oh the sacrifice!
Now you can start mixing your peanut butter stuffing. I messed up this step. You're supposed to blend together the butter and peanut butter, then add the powdered sugar. But I got all excited about sifting...
And I have to say, it worked anyway. Doesn't that look pretty?
Then blend on high until light and fluffy. PS, I'd do this in your largest bowl, too, since powdered sugar likes to drift up!
Wait until your milk chocolate cookies are completely cooled, then frost them.