This is a recipe (or variation thereon) I got from my Aunt and Uncle back in Florida. They are pretty foodie kinda folks, and my uncle is one of those guys that can do just absolutely magical things with a hunk of meat and a grill.
Made this this morning to marinate some bison steaks for a BBQ this afternoon. I'd say the proportions as enumerated below make most of a quart (which you can use as marinade and/or condiment, and which freezes quite nicely).
2 bunches flat-leaf parsley
1 large red onion
1/2 head of garlic (peeled)
juice of 1 lemon
1 cup extra virgin olive oil
1/2 cup red wine vinegar
salt and pepper to taste (I use a tsp of each, more or less)
Peel the garlic, coarsely chop the onion, throw it all in a food processor, and let the good times roll. Easy peasy and delicious to boot. Works especially well on red meat.
Mmmmmmmm... red meat.
Update: Ken K. points out (quite rightly) that a little crushed red pepper is both delicious and appropriate, with which I heartily concur.