In a small pan over medium-low heat, combine the paprika, garam masala, cumin, coriander, turmeric, and cayenne pepper. Toast for about 2 minutes, stirring frequently, until fragrant. Transfer to a blender.
To the blender, add the ginger, garlic, Greek yogurt, lime zest, lime juice, oil, and salt. Blend until a smooth paste forms.
Using a sharp knife, make 2-3 deep slashes into the meaty part of each drumstick. Place the drumsticks in a large bowl, add the marinade, and toss to coat thoroughly.
Cover the bowl and refrigerate for at least 3 hours, or ideally overnight.
Preheat oven to 450°F. Line a baking sheet with heavy duty foil and place an oven-safe rack on top. Grease the rack with nonstick spray.
Arrange the marinated drumsticks on the rack, leaving space between them. Spoon any remaining marinade from the bowl over the top.
Roast for 45 minutes, turning the drumsticks once halfway through, until cooked through.
Turn the broiler to high. Broil the chicken 6 inches from the heat for 3-5 minutes, until the skin is crispy and lightly charred.
Transfer to a platter. Garnish with cilantro and serve immediately with lime wedges and mango chutney.