Meat and Potatoes!

London Broil: David Crane introduced me to this cut of meat; I eyeball about 1/4 lb or slightly less per person, since it's a dense, filling meat--so a little goes a long way, making it awesome for big gatherings. Marinate in a ziploc bag for as long as possible (overnight/all day in the fridge, or a few hours out of the fridge) with: 

balsamic vinegar (at least 1 1/2 cups)

dijon mustard

smashed garlic

salt and pepper

(other possibilities I've used are soy sauce, worcestershire, ketchup, red wine, any sort of dried herbs or spices--just make sure you have plenty of acid in the mixture)

Broil for 5-7 minutes per side, let rest for 10ish minutes, and slice very thinly on the diagonal against the grain.

Potatoes: I'm not a gigant0rz fan of mashed potatoes, but I really like this approach. These measures are approximate, and will feed maybe 12ish people:

Boil until tender in salted water:

8ish medium red potatoes (washed and scrubbed clean but not peeled)

4 garlic cloves

Drain and return to pot; mash! (The garlic will be soft and sweet and easily mashable.)

While you mash, add in approximately:

1, um, regular-size container of sour cream  (I think it's 16 oz)

1/4 to 1/2 cup buttermilk

4 scallions, sliced thinly (white and green parts)

salt and pepper to taste