Preparation Heat oil in heavy large pot over medium-high heat. Add sausage and sautéuntil browned, about 5 minutes. Using slotted spoon, transfer to plate. Add onion and mushrooms to pot; sprinkle with salt and sauté until mushrooms are soft, stirring occasionally, about 7 minutes. Add garlic and thyme; stir 1 minute. Add lentils and bay leaves; stir to coat. Add 6 cups broth; bring to boil. Reduce heat to medium-low, cover with lid slightly ajar, and simmer until lentils are tender, stirring occasionally, about 18 minutes. Return sausage to pot. Add spinach in 2 batches, stirring until wilted. Season with salt and pepper.
Preparation Heat oil in heavy large pot over medium-high heat. Add sausage and sautéuntil browned, about 5 minutes. Using slotted spoon, transfer to plate. Add onion and mushrooms to pot; sprinkle with salt and sauté until mushrooms are soft, stirring occasionally, about 7 minutes. Add garlic and thyme; stir 1 minute. Add lentils and bay leaves; stir to coat. Add 6 cups broth; bring to boil. Reduce heat to medium-low, cover with lid slightly ajar, and simmer until lentils are tender, stirring occasionally, about 18 minutes. Return sausage to pot. Add spinach in 2 batches, stirring until wilted. Season with salt and pepper.