Melt butter a large pot. Add diced onions, smoked sausage, salt, and pepper. Stir occasionally and allow to cook for 2-3 minutes. Add in minced garlic
Add potatoes and then add chicken broth. Season with oregano and cayenne pepper and bring to a boil.
Reduce heat and allow to simmer for 10-15 minutes until potatoes are tender and cooked through. Add in half and half and spinach and cook for 3-4 more minutes before serving.
Notes
Tip: Adding minced garlic too early will cause it to burn so I like to add it in last.