Clean the sweet potatoes well then poke a few holes in the skin with a fork. Bake the sweet potatoes for 45 minutes at 425 degrees.You may need to cook the sweet potatoes for up to 15 minutes longer if you are using particularly large or thick sweet potatoes. You can poke the sweet potatoes with a fork to determine whether they are done. If the sweet potatoes are done, you should be able to press the fork all the way into the potatoes without feeling much resistance.
While the sweet potatoes are cooking, you can start to make the spiced lentils. Mix all of the ingredients for the lentils in a medium pot. Heat the pot over medium high to high heat until the water starts to boil.
Once the lentils start to boil, reduce the temperature to low then put a cover on the lentils. Let the lentils simmer over low heat for 25 minutes.
While the lentils simmer, you can make the lime sour cream. Mix together all of the ingredients for the lime sour cream then put the lime sour cream in the refrigerator until you are ready to use it.
Dice the avocados into cubes and and slice the green onions into thin slices.
When the sweet potatoes are done cooking, slice the sweet potatoes open. Use a fork to mash the flesh of the sweet potatoes then add the lentils and the rest of the toppings to the sweet potatoes.