1Heat the oven to 350°F and spray a 5-by-9-inch loaf pan with nonstick spray.
2Melt the bacon fat in a large, heavy skillet over medium heat. Add the onion and garlic and cook until the onion has softened, about 5 minutes. Take care to not caramelize the onions. Remove from the heat and set aside.
3In a large bowl, combine the remaining ingredients except the turkey. Let sit for 5 minutes, to allow the crumbs to absorb the wet ingredients and soften.
4Add the meat and the onion mixture to the bowl and mix by hand until well combined. Transfer the mixture to the greased loaf pan and bake for about 45 minutes, rotating the pan halfway through the cooking. Let cool before unmolding.