• Heat the oil over medium heat in a large pot or Dutch oven. Season the chicken with salt and pepper and transfer them to the pot. (Don't overcrowd the pot; you might have to do this in batches.) Cook for about 10-12 minutes, flipping the tenders over halfway through, or they reach an internal temperature of 160-165ºF. When done, transfer the chicken to a cutting board.
• Add a little more oil to the pot along with the butter. Add the onions, mushrooms, and potatoes into the pot (see below if you’re using noodles instead) and simmer for about 8-10 minutes, or until they’ve softened, stirring often.
• Add the garlic; simmer for another 30 seconds.
• Pour the marsala wine into the pot. Simmer for a few minutes, deglazing the bottom of the pot with a spatula.
• Stir in the balsamic vinegar; add the broth and the beef base, then bring it all to a boil. Once it reaches a boil, reduce the heat to a low simmer. Add the spinach and shredded chicken.
• With a ladle, scoop about a 1/2 cup of hot broth from the pot and transfer it to a mixing bowl or large measuring cup. Gradually pour in the heavy cream, whisking as you go. Pour the cream into the pot with the rest of the soup and stir.
• Serve with a garnish of chopped fresh parsley and a hunk of fresh bread!

IF USING NOODLES

• In a separate pot, cook the noodles as per the instructions on the package. When the soup is ready, stir the noodles into the pot. Cooking the noodles in the soup will result in mushy noodles and you'll lose liquid as the noodles will absorb the broth, so I don't recommend it.