1 pound455 g sweet Italian sausage, sliced about 1½ inches (4 cm) thick and kept in the casing
1 large onion, chopped
1 garlic clove, finely chopped
10 ounces285 g cremini mushrooms, trimmed and quartered
128-ounce794 g can crushed Italian tomatoes
coarse salt and freshly ground black pepper
finely chopped fresh flat-leaf parsley, for garnish
grated Parmesan or Pecorino Romano cheese, for serving
Instructions
Pour a glug of oil into a large sauté pan (I use an enameled cast-iron Le Creuset) set over medium heat. Add the sausage and cook, stirring, until browned, 7 to 8 minutes. Using a slotted spoon, transfer the sausage to a plate. Scatter the onion into the pan and cook, stirring, until it takes on some color, about 5 minutes. Stir in the garlic and cook for 1 minute, then stir in the mushrooms and cook until they begin to brown and release their liquid, about 10 minutes. Return the sausage to the pan.
Stir in the tomatoes and season with salt and pepper. Reduce the heat to a simmer and cook the stew for 40 minutes. Taste and adjust seasonings as desired. Top with the parsley and Parmesan and serve warm. The stew can be made up to a day ahead and reheated before serving.