1) Place an oven rack in the centre of the oven. Preheat the oven to 190°C/gas mark 5.
2) Spray a 23 by 13cm loaf pan with cooking spray.
3) In a large bowl, stir together the bread crumbs, parsley, sun-dried tomatoes, garlic, if using, eggs, milk, feta, salt, and pepper. Add the turkey and gently stir to combine, being careful not to overwork the meat.
4) Carefully pack the meat mixture into the prepared pan and bake until the internal temperature registers 75°C on an instant-read thermometer, about 45 minutes. Remove from the oven and let rest for five minutes. Transfer to a cutting board and slice. Put on a serving platter and serve.