Make the Scallion Chimichurri sauce: Place the scallions, parsley, oregano, ½ cup olive oil, vinegar, salt, and pepper in a food processor and blend until fairly smooth (or as smooth as you like it) and well combined.
Cut the baguette into 1/2-inch or so slices, but don’t cut all the way through the bread; the goal is for the slices to remain attached at the bottom. (See above or the video for details about using chopsticks along the sides of the bread to prevent slicing all the way down.)
Use a brush to smear the chimichurri sauce in between the slices, making sure to brush some of the sauce on both sides of each slice. Place the baguette on a large piece of foil, and pull the foil up around the sides of the bread, but not over the top — you want the top to be able to brown.
Bake for about 20 minutes until the bread is hot and the top is lightly browned and crusty. Serve hot.
Video
Notes
You can cut a baguette horizontally all the way down the middle, slather the two flat-cut sides with the chimichurri sauce, and bake the garlic bread that way. I usually do almost-slices and let people pull off as many slices as they want. This results in a higher sauce/garlic butter/pesto/what have you to bread ratio, which I think is pretty awesome.The best way to cut a baguette into 1/2-inch or so slices without cutting all the way through the bread is to use chopsticks as a guide. Place one chopstick on each side of the bread. Cut the bread into slices, stopping when the knife hits the chopsticks.