Preheat the oven to 350 degrees F.
Warm the farro in a small saucepan with 2 tablespoons of the butter, 3 to 5 minutes. Season with salt and pepper, and keep warm.
Heat the vegetable oil in a medium skillet over medium-high heat. Sprinkle the cod with salt and pepper, and place, skin-side down, in the skillet. Cover, and cook until the skin is golden and crispy, about 4 minutes. Flip the fillets and transfer the skillet to the oven.
Bake until the fish is cooked, about 4 minutes. Add the remaining 2 tablespoons butter to the skillet and spoon over the fish skin as it melts.
Meanwhile, combine the tomatoes, mint, sea salt, olive oil, balsamic vinegar and basil in a bowl. Season with salt and pepper, toss and set aside.
For each serving, scoop half of the farro onto a plate. Top with a cod fillet and then the marinated tomatoes. Garnish with arugula.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.