Chimichurri Sauce

Chimichurri Sauce
from Food Network's Sunny Anderson

1 bunch fresh parsley
1 bunch fresh cilantro
1 to 2 cloves garlic
1 large red onion, halved and sliced
Kosher salt and freshly ground pepper
2 tablespoons red wine vinegar
3 tablespoons lemon juice
1/2 cup plus 1 tablespoon extra-virgin olive oil
1 pound chuck or top round steak (London broil)
3 poblano peppers, seeded and cut into strips
1/4 cup lager beer
8 8-inch flour tortillas
Lime wedges, for serving (optional)

Combine the parsley and cilantro (leaves and stems), garlic, half of the sliced onion, 1 tablespoon salt, 1 teaspoon pepper, vinegar, 2 tablespoons lemon juice and 1/2 cup olive oil in a food processor; blend into a thick and smooth chimichurri sauce.