Preheat the oven to 325 degrees F.
In a medium bowl, add the meat, 1 small onion, grated on box grater or with handheld flat grater, directly over mixing bowl. Add 2 cloves finely chopped garlic, panko, about 2 tablespoons of the extra-virgin olive oil, the egg, the zest and juice of 1 lemon. Mix to combine. Add the olives, spices, a handful of parsley and a handful of mint. Combine well. Form the mixture into 4 individual rolls and bake on a parchment lined sheet pan until golden brown, about 35 to 40 minutes. The meat loaves may be made ahead and stored; reheat in pan gravy.
Heat a medium shallow pot over medium heat, add 2 tablespoons butter and melt, then add the remaining garlic, and combine. Stir in the zucchini, season with salt and pepper, to taste, and cook for 5 minutes. Add 1 1/2 cups stock to the pan and bring the mixture to a bubble. Add 1 1/2 cups of couscous and remaining handful of chopped mint. Turn off the heat and cover pan. Let stand for 5 minutes, then fluff with a fork.
Meanwhile, heat 2 tablespoons butter to a medium skillet over medium to medium-high heat. Whisk the flour into melted butter, then add the Worcestershire sauce and remaining 1 cup of chicken stock, the remaining lemon zest and juice, 1/4 cup honey, and salt and pepper, to taste. Slide the meat loaves into the sauce. (If the meat loaves are cold, tent with foil and gently reheat in low simmering sauce.) Once the meat loaves are warm, transfer them to a serving plate and raise the heat to high. As soon as the sauce becomes syrupy after 1 to 2 minutes, drizzle it over meat and serve with couscous alongside.