½ cup extra virgin olive oil, divided
1½ cups finely chopped Vidalia onion
2 tbsp chopped garlic
1½ lbs mushrooms, thinly sliced (button, shiitake, portobello, cremini and oyster)
1 tsp soy sauce
1 cup diced carrots
1 cup diced celery
1 cup diced red peppers
10 cups (2.5 L) vegetable stock, divided 1 cup (250 mL) dry red wine
1½ lbs Yukon Gold potatoes, diced
2 tsp dried thyme
2 tsp dried marjoram
1 tsp salt
Pinch of cayenne
½ tsp black pepper
¼ cup unbleached white flour
½ cup tomato paste
In a large skillet, heat ¼ cup (50 mL) oil over medium heat. Add onion; cook 5 minutes or until tender. Stir in garlic; add mushrooms in batches, starting with about 2 cups. When softened, add next batch, cooking each about 5 minutes. Then add soy sauce.
Stir in carrots, celery, red peppers and 1 cup of stock. Simmer for 15 minutes or until softened, covered.
In a large soup pot, combine 7 cups (1.75 L) stock, wine, vegetable mixture including liquids, potatoes, thyme, marjoram, salt, cayenne and pepper. Bring to a boil; cover and reduce heat to a simmer for 10 minutes.
In a small pot, heat ¼ cup oil. Whisk in flour; cook for 1 minute. Add tomato paste; whisk for 1 minute. Add 1 cup vegetable stock; whisk for 1 minute. Add a second cup of stock; whisk for 2 minutes.
Stir into vegetables in soup pot. Cook for 15 minutes on low heat, covered.