1. In a small bowl, combine the soy sauce, sherry, chicken broth, sugar, ginger, and garlic. In another small bowl, stir together the 2 teaspoons cornstarch and the water.
2. Whisk together the egg white and the 2 tablespoons cornstarch. Brush the skinless side of the salmon with the egg-white mixture and then dip it into the sesame seeds to coat.
3. In a large nonstick frying pan, heat the oil over moderately high heat. Put the salmon in the pan, sesame-seed side down, and cook until golden brown, about 5 minutes. Turn and cook until just done, about 3 minutes longer for a 1-inch-thick fillet. Remove.
4. Pour any oil from the pan. Add the soy-sauce mixture. Simmer for 2 minutes, stirring. Whisk in the cornstarch-and-water mixture and cook, stirring, until thickened, about 1 minute longer. Serve the salmon with the sauce poured around it.
Fish Alternatives: Tuna steaks would be perfect with the sesame-seed crust and the sauce. You can also use salmon steaks instead of fillets.
Wine Recommendation: Salmon is generally best with a light red or a substantial white. Pinot noir is the usual red suggested. With the Asian ingredients here, a white such as a pinot gris from Oregon or Alsace in France will make a delicious pairing.