5 medium beets, peeled and cut into 1 1/2-inch wedges
Kosher salt and freshly ground pepper
In a small skillet, toast the cumin seeds over moderately low heat, stirring, until fragrant, 2 to 3 minutes. Transfer the cumin to a mini processor and let cool. Add 1/4 cup plus 3 tablespoons of the oil, the garlic, mustard and honey and process until blended. Scrape the marinade into a resealable plastic bag, add the cubed chicken and refrigerate overnight.
Preheat the oven to 400°. In a baking dish, toss the beets with the remaining 1 tablespoon of oil; season with salt and pepper. Cover with foil and bake for 35 minutes, or until tender. Let cool.
Light a grill. Thread alternating chicken cubes and beet wedges onto bamboo skewers. Brush lightly with oil and season with salt and pepper. Grill the kebabs over moderately high heat for 10 to 12 minutes, turning and brushing occasionally, until the chicken is cooked.