Preheat oven to 400°F.
In a large bowl, combine the chicken, harissa, cumin, paprika and a large pinch of salt and pepper until well incorporated. Cover with plastic wrap and chill for at least 30 minutes or overnight. If you chill overnight, let the chicken sit for 30 minutes at room temperature before cooking.
Set a very large pan over medium heat. Once hot, drizzle in 3 tablespoons olive oil and add in half of the chicken. Cook until golden brown on both sides, about 3 to 4 minutes per side. Transfer to a platter and continue browning the second batch.
Once all of the chicken has browned, drizzle the remaining oil into the hot pan. Stir in the onion, garbanzo beans, and radishes. Season with a pinch of salt and pepper and cook until softened, about 5 minutes. Add the chicken stock to the pan and use a wooden spoon to scrape up all of the browned bits from the bottom of the pan. Set the chicken back in, in an even layer as best as possible. Bake until the chicken has cooked through and registers 165°F, about 25 to 30 minutes (depending on the size of your drumsticks).
Meanwhile, in a small bowl, whisk together the labneh, lemon juice and a pinch of salt and pepper. Chill until ready to use.
Once the chicken is done, carefully remove the pan from the oven and let rest for about 10 minutes. Before serving, drizzle or dollop the top with the labneh and top with any and all of the herbs. Serve with a squeeze of fresh lemon juice. Enjoy!