- 3 large eggs
- 1 1/2 cups chicken broth
- 2 teaspoons mirin
- 1 teaspoon soy sauce such as Kikkoman
- 1 teaspoon freshly grated lemon zest
- 4 medium shrimp
- 1 scallion
- 1 large mushroom
- In a bowl with a fork beat eggs until combined well. Skim any fat from broth and add broth with mirin, soy sauce, and zest to eggs, stirring to combine well. Pour custard through a fine sieve into another bowl.
- Peel shrimp and devein if desired. Diagonally cut white and pale-green parts of scallion into thin slices and thinly slice mushroom.
- Divide shrimp, scallion, mushroom, and custard among four 1/2-cup custard cups or ramekins and cover each tightly with foil. Arrange cups or ramekins in a steamer over boiling water and steam custards, covered, over high heat 2 minutes.
- Reduce heat to moderate and steam custards, covered, until set, about 10 minutes more.
- Serve custards immediately.