In a large bowl stir together the cumin, chili powder, garlic powder, salt, pepper, nutmeg, paprika, 1 tablespoon olive oil and beer. Add the chicken cubes. Cover and allow to marinate for 2 hours and up to 12.
Preheat the oven to 400.
Add the grape tomatoes and onions to a baking sheet, drizzle with olive oil, sprinkle with salt and pepper, toss to coat. Roast for 10-12 minutes or until blistered.
Remove chicken from the marinade, pat dry.
Add the remaining 1 tablespoon olive oil to a cast iron skillet over medium high heat until hot but not smoking.
Add the chicken, cooking on all sides until cooked through.
Transfer the chicken to a serving platter, top with tomatoes and onions.
In a small bowl stir together the yogurt, lemon juice, cilantro, mint, garlic powder, salt and pepper to taste. Serve yogurt sauce along side chicken and tomatoes.