Heat a large pot over medium-high heat and spray with oil.

Add the sausage links, crumble, and cook until browned, about 7 minutes. Using a slotted spoon, remove the sausage and set aside.

Immediately add 1 teaspoon oil, then the onion and garlic. Cook until softened, about 5 minutes.

Add Italian seasoning and stir well to coat. Add beans and broth, stir to combine.

Use an immersion blender to blend soup until creamy, or transfer to a blender and puree. Return to pot.

Add cooked sausage, potatoes, salt, and pepper. Bring to a boil.

Reduce heat, cover, and simmer for about 30 minutes until potatoes are tender.

Stir in the chopped spinach, cook for 1 minute, then serve hot.