Place a 10- to 12-inch nonstick frying pan over high heat. When pan is hot, add tuna and cook on each side, turning once, until browned on the surface, gray to about 1/4 inch in, and still red in the center (cut to test), 4 to 5 minutes total.
Spoon noodle mixture equally onto plates and top with tuna.
Mix soy sauce and sesame oil, then drizzle over tuna to taste.
Chinese noodles with shiitakes: In a 10- to 12-inch nonstick frying pan over high heat, stir 1/2 pound stemmed, rinsed, drained, and sliced fresh shiitake mushrooms, 1/2 cup chopped onion, and 1 tablespoon minced fresh ginger until onion is limp, about 5 minutes.
Add 2 cups fat-skimmed chicken broth, 2 cups water, and 1 pound rinsed and drained fresh Chinese, Shanghai-style, or udon noodles (about 1/4 in. thick). Bring to a boil and stir occasionally until noodles are barely tender to bite, 6 to 7 minutes. Meanwhile, rinse, stem, and string 1/2 pound Chinese pea pods.
Add to pan, stir, and cook 1 minute more. Stir in 1/3 cup prepared oyster sauce and 2 teaspoons Asian (toasted) sesame oil.
Buckwheat noodles with macadamias: In a 10- to 12-inch nonstick frying pan over high heat, frequently stir 1/3 cup coarsely chopped roasted, salted macadamia nuts until golden brown, 3 to 4 minutes.
Pour from pan; set aside. In same pan over high heat, bring 1 1/2 cups fat-skimmed chicken broth and 2 cups water to a boil.
Add 1/2 pound dried buckwheat noodles (soba) and cook until just tender to bite, 6 to 7 minutes. Stir in 3 tablespoons lime juice, 1/3 cup thinly sliced green onions, and 1/4 cup chopped fresh cilantro.
Sprinkle each serving with macadamias and garnish with cilantro sprigs and lime wedges.
Spinach noodles provenal: In a 10- to 12-inch nonstick frying pan over high heat, stir 1 tablespoon olive oil, 6 minced drained anchovy fillets, 3 minced cloves garlic, and 1 cup sliced onion until onion is limp, about 5 minutes. Stir in 1 can (28 oz.) diced tomatoes with juice, 2 cups water, 1/2 pound dried spinach noodles, 1/2 cup chopped pitted calamata olives, and 1 tablespoon chopped fresh thyme leaves. Stir occasionally until noodles are just tender to bite, 10 to 12 minutes. Stir in 1/4 cup chopped parsley.
