Chicken, Rice and Mushroom Soup with Lime

3 cups white chicken stock, or 1 1/2 cups frozen concentrated plus 1 1/2 cups water
3/4 cup cooked white or brown rice
1/2 cup shredded cooked chicken
Salt and pepper to taste
10 white mushrooms, wiped clean, trimmed, and sliced thin
3 scallions, sliced thin
1 egg yolk
Juice of 1 lime
Minced fresh herbs, whatever you have around


Bring chicken stock to simmer over medium heat. Stir in rice and chicken shreds. Season to taste with salt and pepper and bring back to the simmer. Add sliced mushrooms and simmer 3 minutes. Add scallions and simmer 1 minute. Whisk together egg yolk and lime juice in small bowl. Ladle some hot soup into bowl containing egg yolk mixture while whisking constantly. Stir this tempered? egg mixture into pot and simmer 1 more minute until soup thickens. Serve immediately.