1. Prepare pilaf mix according to package directions. Preheat oven to 400°F. In a frying pan, heat 1 1/2 tablespoons of olive oil. Add onion and cook over medium heat until softened, 3 to 5 minutes. Add garlic and cook 1 minute. Stir in half of mint. Toss with cooked pilaf.
2. Fill chicken cavity with pilaf. Brush skin with remaining 1 tablespoon oil. Season skin with salt and pepper and tie legs together with kitchen string. Place chicken, breast side up, on a rack in a shallow roasting pan. Roast 30 minutes. Reduce oven temperature to 350° and continue to roast until an instant-reading thermometer inserted into the thigh registers 180°, about 1 1/2 hours longer.
3. Remove chicken from pan and pour off all but 2 tablespoons of drippings. Add flour to pan and cook over direct heat, stirring, for about 2 minutes, until lightly colored. Whisk in broth and remaining mint and cook, stirring, until thickened and bubbly, 2 to 3 minutes. Season with additional salt and pepper to taste.
4. Spoon stuffing into a serving bowl. Carve chicken and serve with stuffing and gravy.