1Heat olive oil in a large frying pan over medium heat. Cook onion, celery, carrot, zucchini, mushrooms and garlic for 3-4 minutes or until soft. Add red wine and cook until most of the liquid evaporates.
2Transfer to slow cooker and add all other ingredients.
3Cook on low for 8-10 hours or until lentils are soft (add more water if required).
4To make polenta, bring almond milk and water to a simmer in a large saucepan over medium heat. Gradually whisk in polenta and salt. Reduce heat and simmer, stirring occasionally, for 30 minutes or until mixture thickens and polenta is soft (i.e. no longer has a grainy texture). Stir through nutritional yeast, if using.
5Divide polenta among bowls and top with bolognese. Garnish with parsley and serve.