Prepare the spice mix: Combine salt, garlic powder, black pepper, red chili pepper, onion powder, cumin powder (optional), ginger powder, and paprika in a bowl. Mix well.
Prepare the chicken: Pat the chicken drumsticks dry with paper towels. Place them in a large bowl. Spray or lightly coat with avocado or olive oil to help spices stick.
Season and coat the chicken: Sprinkle some of the spice mix directly over the chicken. Mix the remaining spice mix into the flour. Coat each chicken drumstick thoroughly with the spiced flour mixture.
Prepare the vegetables: Wash and cut broccoli, zucchini, eggplant, carrots, potatoes, onions, and garlic into bite-sized pieces. Slice potatoes thinly to ensure even cooking.
Season the vegetables: Place the cut vegetables in a bowl. Drizzle with olive oil and sprinkle with the remaining spice mix. Toss well to coat evenly.
Bake the chicken: Preheat the oven to 380°F (193°C). Arrange the coated chicken drumsticks on a baking tray. Bake for 50 minutes, turning halfway through to ensure even cooking.
Bake the vegetables: Place the seasoned vegetables on a separate baking tray or alongside the chicken if space allows. Bake in the oven for about 30-50 minutes, checking for tenderness and doneness.
Serve: Once the chicken is cooked through and vegetables are tender, remove from the oven. Serve the oven-fried chicken with the roasted vegetables as a wholesome meal.