Preheat the oven to 400 degrees F. Poke several holes in each sweet potato using a fork and wrap with foil. Place foil-wrapped sweet potatoes on a baking sheet and roast until very soft, about 60 to 80 minutes (depending on the size of the sweet potatoes).
While the sweet potatoes are roasting, prepare the guacamole by mashing all of the ingredients in a bowl to desired consistency (I like leaving mine slightly chunky). Refrigerate until ready to use.
Stir together all of the ingredients for the Dukkah in a small bowl. Set aside until ready to use.
When sweet potatoes have finished baking, allow them to cool enough to handle, then unwrap them and cut a long slit down the center. Use a fork to dig a well in each potato and sprinkle the flesh with sea salt.
Stuff each sweet potato with desired amount of black beans (I heat mine up on the stove top first) and guacamole. Sprinkle with pistachio Dukkah spice blend and serve with chopped green onion and fresh cilantro.