Preheat the oven to 350°F.
In a large bowl, whisk together the lime juice, vinegar, salt and water. Add the vegetables and herbs and toss to coat fully. Rest for 1 hour and up to overnight.
Place the smashed garlic cloves, mint, peppercorns, bay leaf, star anise and lemon zest in a cheesecloth sachet and tie closed.
Place the lamb, herb sachet, lemon juice, 1 teaspoon salt and enough vegetable stock to come halfway up the sides of the meat in a braising dish. Cover tightly and braise for 2-3 hours, until the meat is very tender.
Meanwhile, make the Colorado sauce. Heat the oil in a large pot over medium heat. Add the onion and cook until translucent. Add the garlic, oregano, serranos and cook until fragrant, 2-3 minutes. Add the roasted red peppers, paprika, chili powder, cinnamon and cumin, and cook for another 2-3 minutes.
Stir in the stock, achiote paste, diced tomatoes and salt. Bring to a boil, then reduce the heat and simmer until reduced by 1/3. Adjust the seasoning to taste. The sauce should be slightly spicy with a silky texture.
To make the rice, in a large pot, combine the rice with 2 cups water, a pinch of salt, tomato paste, garlic, onion, paprika and cumin. Bring to a simmer, turn the heat to low, cover and simmer for 40-45 minutes, or until the grains are tender. Fluff the rice and squeeze in the lime juice.
When the braise is finished, remove the meat from the braising liquid and skim any fat off the surface of the liquid.
Heat a large skillet over medium-high heat. Place the lamb and the defatted braising liquid into the skillet. When the lamb is sizzling and most of the liquid has evaporated (8-12 minutes), add the Colorado sauce. Bring to a simmer and cook for 12-15 minutes, until reduced and the sauce is coating the lamb.
Divide the rice between bowls and top with lamb, sauce, slaw, pumpkin seeds, sour cream and cilantro.