For the chimichurri: In a food processor, combine the parsley, cilantro, oregano, garlic, shallot, cumin, pepper flakes, salt, red wine vinegar and honey. With the food processor running, slowly add the olive oil; the final product should be smooth but still have a bit of texture to it.
For the rice and black beans: Heat the grapeseed oil in a pot over high heat. Add the rice and coriander and cook, stirring, to toast the rice, about 2 minutes. Add the vegetable stock and bring to a simmer. Reduce the heat to low and cook, covered, until the liquid is absorbed, 10 to 12 minutes.
Once the rice is cooked, remove it from the heat and fluff with a fork. Mix in the black beans, cilantro, lime juice, salt and pepper.
For the smoked tomato salsa: Prepare a smoker with soaked wood chips (cherry or apple wood preferred) and heat to 350 degrees F.
Place the tomato halves, onion quarters, garlic and jalapeno in a pan. Transfer to the smoker and cook until the onions are tender, 20 to 30 minutes.
Dice half of the onions and half of the tomatoes. In a food processor, puree the remaining onions and tomatoes along with the jalapeno, garlic and the lime juice.
In a bowl, mix the pureed sauce with the diced onions and tomatoes and the chopped cilantro. Season to taste with salt and pepper.
For the lemon aioli: In a food processor (or using an immersion blender) combine the lemon juice, mustard, egg, egg yolk and garlic; puree until smooth. With the motor running, slowly add the olive oil to emulsify the aioli. Season to taste with salt and pepper.
For the flank steak: Cut the flank steak into six equal portions, slicing against the grain and on an extreme bias. With the back of a knife, tenderize the steaks by pounding them out on both sides. Season on both sides with salt and pepper.
Heat a cast-iron skillet over high heat until smoking. Add just enough grapeseed oil to coat the pan. Working in batches, sear the steaks on both sides, about 2 minutes. Remove the steaks to a plate to rest before plating.
To plate: Divide the rice and beans between six plates, mounding it in the center of each plate. Spoon about 2 ounces of the salsa over the top and then lay a steak over the rice. Drizzle some chimichurri over the steak.
In a bowl, dress the watercress with lemon aioli. Top the steaks with the dressed watercress. Serve.