This is what I put in mine:
Red Bell Pepper, Red Onion, Corn, Chiles, Jalapeno Pepper, Garlic
Doesn't it look good?!? I got this great recipe from Pioneer Woman. Mark and I absolutely love it! You should try it sometime (along with the rest of her delicious home cookin' recipes).
So, what I want to know is what do YOU put in YOUR mac & cheese?!