In stock pot or enameled dutch oven heat sesame oil. Add julliened mushrooms and pork and sautee until pork just browned
Add stock, white pepper, soy sauce, vinegar, and siracha simmer until just about boiling
Make slurry with cold water and corn starch. Stream in while stirring soup
Bring just to boiling point so corn starch thickens the soup.
While stirring in a slow clockwise direction stream in the beaten eggs
Add scallions and serve