Rub tuna steaks with oil and season with salt and pepper. Set aside. In a small saucepan, heat remaining 2 tsp. oil over moderately high heat. Add the garlic and ginger and cook, stirring until slightly colored, about 1 minute. Stir in the stock, vinegar, soy sauce and 1 tsp. of the lemon zest. Add the chile and sugar and bring to a boil. Remove from the heat and stir in the scallions and keep warm. Bring a pot of water to the boil for the noodles. Grill the tuna for about 5 minutes, turning once, until charred on the outside and pink in the middle. Transfer to a plate and keep warm. Cook the noodles and toss with half of the soy sauce mixture. Mound the noodles on 8 warm plates. Place the tuna on the noodles and spoon the remaining sauce over. In a small bowl, toss the remaining zest with the chives and minced mint and sprinkle over each serving. Garnish with mint and serve immediately. Source:Food and Wine November 1992.