Pat the chicken dry and season all over with 2 teaspoons kosher salt and 1 teaspoon black pepper. Set aside.
In an oven-proof wide skillet or braising pot, heat 1 tablespoon of extra virgin olive oil over medium-high heat until very hot.
Add the chicken, skin-side down and cook for 5 minutes until well-browned and crispy. Flip and cook for 2 to 3 minutes more. Transfer the chicken to a plate and drain off all but 1 tablespoon of chicken fat from the pot. Return the skillet to medium heat.
Sauté the aromatics:
Add the leeks and the peppers to the skillet and cook, stirring often, for 5 to 6 minutes or they soften. Add the garlic and cook for 1 minute until fragrant.
Reduce the heat to medium-low. Sprinkle 2 tablespoons sweet paprika, 1½ teaspoons smoked paprika, and ½ teaspoon cayenne powder over the vegetables and toss to coat.
Prepare the sauce:
Sprinkle the flour over the vegetables and stir to coat. If the pot seems dry, add a teaspoon or two of the reserved chicken fat. Cook for 1 minute until the paprika begins to deepen in color, being careful not to burn the spices.
Slowly stir in the chicken stock until completely smooth. Bring to a boil and add the crushed tomatoes. Turn off the heat. Add 1 teaspoon of sugar. Taste and season with salt and pepper.
Roast the chicken:
Nestle the chicken into the sauce. Transfer to the oven and roast for 25 to 30 minutes or until an instant-read thermometer reaches 165ºF when inserted into the deepest part of the thigh. Remove from the oven.
To serve:
Scatter minced parsley over the chicken. Serve with cooked pearl couscous, rice, or egg noodles and a lemon wedge. Enjoy!