For the chimichurri: Place parsley, oregano, garlic, vinegar, red pepper flakes, and salt in a food processor and pulse until finely chopped; scrape down the sides of the bowl as needed. With the motor running, add oil in a steady stream. Measure out ¾ cup of sauce and transfer the remaining sauce to an airtight container and refrigerate at least 2 hours or up to 1 day to allow the flavors to meld. (The chimichurri will keep in the refrigerator for up to 1 week.)
For the crostini: Lightly brush both sides of the baguette slices and toast on grill over medium high heat until toasty golden on both sides. (You can do this ahead of time and store in an air-tight container until ready to serve.)
For the steak: Place the hanger steaks in a large ziptop bag and pour in the remaining chimichurri. Massage to make sure everything is coated and place in the refrigerator overnight (or for at least 6 hours).
Remove the steak from the marinade and pat dry with paper towels. Season with kosher salt and pepper the let come to room temperature for about 45 to 60 minutes. Preheat grill to high. Brush and oil grates before cooking. Lay steaks on the grill at a 45° angle to the grates and cook for 4 to 5 minutes, flip and cook for 4 to 5 minutes more for medium-rare. Hanger steak is at it’s best when cooked medium-rare to medium. Use a digital thermometer and pull it somewhere between 125°F and 130°F. Remove and let rest 10 minutes tented with aluminum foil before slicing across the grain of the meat.
For serving: Slice steaks across the grain of the meat right before building appetizers. Spread crostini with softened goat cheese. Top with a slice of hanger steak and a small spoonful of chimichurri.
Recipe by Grilling Outdoor Recipes powered by Bull Outdoor Products at http://www.grillingoutdoorrecipes.com/easy-grilled-appetizer-hanger-steak-crostini-with-chimichurri/