Melt butter in a large Dutch oven over medium-high heat. Add onion, porcini mushrooms, tarragon, thyme, and bay leaf; sauté 10 minutes or until onions are lightly browned. Add garlic, and cook 2 minutes, stirring frequently. Add wine, scraping pan to loosen browned bits. Add 1 teaspoon salt, pepper, button mushrooms, and cremini mushrooms. Cook 10 minutes, stirring occasionally.
Place bread in a food processor; pulse 5 times or until crumbly. Add the breadcrumbs, water, and bouillon cube. Reduce heat; simmer 20 minutes. Discard bay leaf.
Place about 2 1/2 cups mushroom mixture in a blender; process until smooth. Pour pureed soup into a large bowl. Repeat procedure with remaining mushroom mixture, 2 1/2 cups at a time. Stir in 1/2 teaspoon salt and half-and-half. Top each serving with 1 teaspoon chives. Yield: 6 servings (serving size: 1 1/3 cups).
Wine note: In Europe, rich soups such as this creamy, earthy mushroom soup are often served with a dry amontillado Sherry. If you've never tried this classic combination, now's the time. Osborne Amontillado "Coquinero" Sherry nonvintage from Jerez, Spain ($16) is a great choice. -Karen MacNeil