Preheat the oven to 425 degrees F.
Heat the olive oil in a medium saute pan. Add the onions and garlic and cook over medium-low heat, stirring occasionally, for about 6 minutes, until the onions are translucent but not brown. Season with salt and pepper.
Add the tomato paste, Worcestershire and 2 tablespoons of the harissa to the onion, stir to combine.
In another bowl, beat the eggs and add the panko, milk and parsley and whisk to combine. Add the onion mixture and stir to combine. Add the turkey, season with kosher salt and pepper and mix lightly with a fork. Don't mash or the meat loaf will be dense.
Shape the mixture into an oval or rectangular loaf on a sheet pan covered with parchment paper.
In a small bowl, stir to combine the ketchup with the remaining 2 1/2 tablespoons of harissa. Spread the mixture evenly on top. Bake for 40 to 45 minutes, until the internal temperature is 165 degrees F and the meatloaf is cooked through. *Optional: A pan of hot water in the oven, under the meatloaf, will keep the top from cracking.
