In a large pot or Dutch oven over medium-high heat, brown vegan Italian sausage, breaking it up into crumbles. Remove cooked sausage to a paper towel-lined plate.
Add diced onion to pot and sauté until onion is translucent, about 3-5 minutes. (If the brand of vegan sausage you're using is lower in fat, you can drizzle in some olive oil to sauté. For brands like Beyond Meat you can simply sauté in the drippings.)
Add in minced garlic and sauté for about a minute.
Add in the cubed potatoes, vegetable broth, and bay leaf. Bring to a boil, then reduce heat to low/medium-low and simmer for 10-12 minutes, or until potatoes are easily pierced with a fork.
Stir in chopped kale and simmer for an additional 3-5 minutes, until wilted and tender. (If using spinach instead, add in the next step.)
Stir in vegan sausage crumbles and vegan heavy cream. Bring the soup to a very gentle boil for about a minute to heat everything through. Taste and season to preference with salt and pepper. (How much salt will depend on your brand of vegetable broth.)
Garnish with fresh parsley, vegan parmesan, and optional vegan bacon crumbles. Serve with crusty bread.