In a pot over medium heat, add the diced onion and bacon. Cook for 5-6 minutes until the onions are soft. Add the garlic and cook for another minute until fragrant.
Add the chopped celery, carrot, and potatoes. Add the bay leaf and pour in the chicken stock. Bring the mixture to a boil and then turn it down to let it simmer. Let it cook until the soup thickens and the potatoes are tender but still holding their shape.
Meanwhile, brown the sausages on a skillet until golden. Season the soup for salt and pepper. Stir in the sour cream of heavy cream right before serving. Top with sausages and chopped herbs.