Remove excess fat from the chicken pieces. Rub a generous amount of salt, garlic powder and red pepper on both sides of each piece, making sure each is evenly covered. Let stand at room temperature for 30 minutes.

Meanwhile, in a medium-size bowl combine the onions, bell peppers and celery; set aside.

Combine the flour, ½ teaspoon salt, ½ teaspoon garlic powder and ½ teaspoon red pepper in a paper or plastic bag. Add the chicken pieces and shake until chicken is well coated. Reserve ½ cup of the flour.

Place the chicken pieces in a baking pan (do not crowd) and bake for ~40 min at 375° to 400° until nicely browned. Half way through turn the pieces over to let them brown on both sides.

Pour ½ cup of oil into a large heavy skillet. Place the skillet over high heat. Using a long-handled metal whisk, gradually stir in ½ cup flour. Cook, whisking constantly, until roux is dark red-brown to black, about 3½ to 4 minutes, being careful not to let it scorch or splash on your skin. Remove from heat and immediately add the reserved vegetable mixture, stirring constantly until the roux stops getting darker.

Return pan to low heat and cook until vegetables are soft, about 5 minutes, stirring constantly and scraping the pan bottom well.

Meanwhile, place the stock in a 5½-quart saucepan or large Dutch oven. Bring to a boil. Add roux mixture by spoonfuls to the boiling stock, stirring until dissolved between each addition. Return to a boil, stirring and scraping pan bottom often. Reduce heat to a simmer and stir in the andouille and minced garlic. Simmer uncovered for about 45 minutes, stirring often toward the end of cooking time.

While the gumbo is simmering, bone the cooked chicken and cut the meat into ½-inch dice. When the gumbo is cooked, stir in the chicken and adjust seasoning with salt and pepper. Serve immediately.

To serve as a main course, mound ⅓ cup cooked rice in the center of a soup bowl; ladle about 1¼ cups gumbo around the rice.