Preheat your oven to 350°F (175°C) and grease a 9x5-inch loaf pan.

In a skillet over medium heat, melt 2 tablespoons of unsalted butter and sauté the diced yellow onion, carrots, and celery for about 6–8 minutes.

Sprinkle kosher salt and freshly ground pepper into the sautéed vegetables and mix in 3 tablespoons of gravy. Let this mixture cool.

In a mixing bowl, combine ground turkey, stuffing mix, and eggs. Fold in the cooled vegetable mix and drizzle in milk, seasoning to taste.

Transfer the meat mixture to the greased loaf pan, shaping into a smooth loaf. Pour the remaining gravy over the top.

Bake for about 40 minutes until the top is golden brown and a meat thermometer reads 165°F (74°C).

Let the meatloaf rest for a few minutes before slicing and serve with additional gravy drizzled on top.