Updated Monday, April 15th, 2013
While visiting Vermont's Woodstock Inn, Senior Food and Home Editor Amy Traverso tasted this soup and thought it so delicious she declared it the best soup she's ever had. Make it and taste for yourself why it shut down all the conversation at the table. She says it's "creamy, a bit sweet from the onions, but balanced by a wonderful savoriness that reminded me of a great French onion soup."
Special thanks to Chef Greg Farrell at The Woodstock Inn for sharing the recipe with us.
Heat oil in a large pot or Dutch oven over medium heat, then add onions, garlic, and 1 teaspoon kosher salt. Stir, cover, and cook 5 minutes. Remove cover, reduce heat to medium-low, and cook, stirring occasionally, until onions turn a deep golden brown, 20 to 25 more minutes. Add sherry and brandy, increase heat to medium-high, and cook until liquid is reduced by half. Add potato and thyme, stir, then add cream and beef broth. Bring to a boil, then reduce heat to low and simmer until potato is very tender, about 10 minutes. Puree soup in batches in a blender (or process with an immersion blender), then return to a simmer. If the soup seems too thick, add a bit more broth.
In a medium bowl, toss the Gruyère with the corn starch then whisk it into the soup with the Parmesan and Romano (if using). Check seasonings and add pepper and additional salt to taste. Garnish with chives and serve hot. Yield: 6 to 8 servings
Two cups of cream is not unusual for restaurant fare, but it's still a lot of cream, and you might not want to use that much at home. We think 2 cups of broth and 1 cup of cream is still creamy and delicious. You could reduce the amount further, to 1/2 cup cream and 2 1/2 cups broth, if you'd like. You can also reduce the amount of Gruyère to 2 ounces and use either the Parmesan or the Romano cheese. You don't "need" both.
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