Fill a shallow bowl with the flour and set aside.
Place breadcrumbs in a large bowl and stir in 2 tablespoons of Marsala.
Add parmesan, egg, parsley, 1 teaspoon salt, and 1/4 teaspoon pepper to the breadcrumb mixture and mix to combine.
Mix the ground turkey into the breadcrumb mixture (I use my hands).
Wet your hands with cold water and shape the mixture into 1-inch balls.
Roll the meatballs in the flour. Refrigerate the meatballs while you cook the mushrooms and shallots.
Heat a wide skillet over medium heat. Add 1 tablespoon of olive oil and 1 tablespoon of butter and heat until the butter melts. Add the mushrooms and cook until they start to brown, about 5 minutes.
Add shallots and cook until shallots are soft and lightly brown, about 5 minutes. Remove the mushrooms and shallots from the pan and set aside.
In the same pan, heat 1 tablespoon of olive oil. Add half the meatballs and lightly brown the meatballs, shaking the pan as needed to brown on all sides. Remove meatballs from the pan. Add another tablespoon of oil to the pan. Add the remaining meatballs and cook until lightly browned on all sides. Remove meatballs from the pan.
Pull the pan off the heat and add half the Marsala. Place the pan back on the heat and use a wooden spoon to scrape the bottom of the pan. Add the remaining Marsala and cook until it is reduced by half.
Add the chicken stock and meatballs to the pan. Bring to a simmer and cook until meatballs are cooked and sauce begins to reduce and thicken, about 10 minutes.
Add the mushroom mixture to the pan and continue simmering until heated. Turn off the heat and swirl in one tablespoon of butter.
Sprinkle with parsley and parmesan.
