Three-Onion Soup

Directions

1. 1
   Saute the yellow and red onions and the leeks in the butter and olive oil in a large soup pot over high heat for 510 minutes, stirring occasionally to keep the onions from sticking to the bottom of the pot and burning.
2. 2
   When the onions have begun to soften slightly and reduce in volume, 510 minutes, lower the heat to medium and continue to saute them for about an hour, until they are caramel in color and almost melted.
3. 3
   You dont want the onions to burn, so, if it looks like theyre heading in that direction, lower the flame even more, or splash a little bit of water over themthis buys you some cooking time.
4. 4
   Sprinkle the onions with the flour, stirring all the while so the flour doesnt clump.
5. 5
   Saute for another 5 minutes to cook off the floury taste.
6. 6
   Pour the stock over the onions and bring it to a boil over high heat.
7. 7
   Reduce the heat and simmer for 30 minutes.
8. 8
   Stir in the Worcestershire sauce, salt, and pepper.
9. 9
   Just before youre ready to serve the soup, whisk in the cheese.
10. 10
    Its important to whisk in the cheese at the last minute, or else the cheese will fall to the bottom of the pot and burn.
11. 11
    Serve warm.