In a small bowl, combine the coriander, paprika and salt. Pat the chicken thighs dry with paper towels, season on both sides with the spice mixture and place in a gallon-size zip-top bag. Refrigerate for several hours but preferably overnight.
Prepare and preheat your lump charcoal grill to create two heat zones: high and low.
Brush the chicken thighs with olive oil and place them skin-side down on the hot side of the grill. Cover and cook for 2 minutes. Uncover and move the chicken to the low side of the grill, skin-side up. Cover and cook until the thighs reach an internal temperature of 160 degrees F, 15 to 20 minutes. Pour half the Blackberry BBQ Sauce into a medium bowl and use it to baste the chicken occasionally during the final 10 minutes of cooking.
Remove the chicken from the grill. Serve with the remaining sauce on the side.
Blackberry BBQ Sauce
Yield:about 2 quarts
In a large saucepan, combine the blackberries, beer, vinegars, sugar, onion, garlic, habanero, chipotle powder, coffee, coriander and cumin. Cook over medium-low heat, stirring occasionally, for 2 hours. Carefully puree the sauce in a blender or food processor, then strain.