Using a mortar and pestle, crush cumin seeds until finely ground. Add garlic to the mortar and pestle, then pound until the garlic and cumin have made a paste (Alternatively you could use 3/4 teaspoon ground cumin and 3 minced cloves garlic if you do not have access to mortar and pestle. The flavor will not be as strong, but still very good.) Stir in the oregano, sea salt and 2 teaspoons olive oil. Rub this into the pork shoulder really well using your hands. Place pork into a large ziploc bag and pour in citrus juice. Seal, then massage a bit to work the juice throughout the pork. Place bag in the refrigerator and let marinate for at least 6 hours, best if overnight.
After it has marinated, preheat oven to 225 degrees F or turn on slow-cooker to low. Then heat remaining 1 tablespoon olive oil in a large dutch oven to medium high (something big enough so that the meat can lay flat inside it). Sear pork shoulder on both sides for 4 minutes, until slightly browned. Add leftover citrus juice from the bag to the dutch oven, then place in oven, covered, and roast for 6-8 hours, basting with its own juices every 2 hours. OR you can add the seared pork and remaining citrus juice from bag into the slow-cooker and roast on low for 6-8 hours, basting with its own juices every 2 hours. When done roasting, shred the pork in its own juices and transfer to a container.
The lentils and vegetables can be made ahead of time if you are cooking the roast in the oven, or while the roast is in the slow-cooker if you are using that method.
Preheat oven to 400 degrees. Rub 2 tablespoons olive oil and 1/4 teaspoon salt into the sliced sweet potato rounds, then spread evenly onto a sheet pan so they are not touching. Place trimmed beets into a large piece of aluminum foil and enclose, making a packet for them. Place sweet potatoes and beets into the oven. Roast potatoes for 25 minutes or until browned, turning them over halfway through so both sides are evenly cooked. Leave beets in the oven for another 40 minutes, until they are easily pierced with a fork. Remove from oven, let cool, then peel away skins under cold running water. Cut peeled beets into small cubes and toss with 1/4 teaspoon salt.
While those vegetables are roasting, make the lentils and kale. For lentils, add water to a medium saucepan and bring to a boil. Add lentils and cook for 22-25 minutes while just simmering, until lentils are soft to the bite, but not mushy. Drain lentils and stir in remaining 1 tablespoon olive oil and 1/4 teaspoon salt. Set aside
For kale, add the thin strips to a large saute pan and add 1 tablespoon water and 1/4 teaspoon salt. Cook on medium, stirring throughout, until leaves are wilted, about 5 minutes. Set aside. To assemble each bowl, distribute pork, sweet potatoes, beets, kale and lentils among each then top with minced cilantro, sliced radish and big squeezes of lime (key for flavor). Enjoy!