Mix the buttermilk with the salt, pepper, curry, turmeric, and cumin
Place the brine in a large bag (or bucket)
Add the whole chicken and place in the refrigerator
Let the chicken sit overnight
Preheat the BGE to 375° measured at the dome
Spatchcock the chicken and place on a raised grid
Cook for an hour to an hour and a half (or until the chicken measures 165°)
Let the chicken rest, slice, serve