1. Preheat oven to 425 degrees F. Pierce sweet potatoes with a fork and place on the bottom rack of the oven until tender.
2. While sweet potatoes bake, chop top off head of garlic, exposing the tip of each clove. Coat cut side with 1 teaspoon olive oil, and tightly wrap in aluminum foil. Place in oven with sweet potatoes and roast until brown and tender (1 hour).
3. While garlic roasts, toss cauliflower with 1/2 tablespoon olive oil and place in a baking dish. Place tomatillo and peppers on a baking sheet and toss with 1/2 tablespoon olive oil. Sprinkle with 1/2 teaspoon salt. Add both to top rack of oven and roast until cauliflower is brown and tomatillos are reduced to sauce (35-45 minutes).
4. While vegetables are roasting, heat remaining 3 teaspoons of oil in large saucepan over medium-low heat. Saute onions until soften (5-8 minutes). Stir in cumin, oregano, thyme, and remaining 1/2 teaspoon salt.
5. Add roasted vegetables and garlic (don't add sweet potatoes), zest, tequila, and beans and cook until heated through (5-10 minutes). Pour over baked sweet potatoes and garnish with cilantro to serve.