For the sweet potato, heat oven to 425. Line a rimmed metal baking sheet with parchment paper. Lightly coat your sweet potato in olive oil, then season the skin with salt. Bake for 50 minutes or until tender. Test by inserting a sharp knife into the sweet potato—there should be little to no resistance.
For the tahini sauce, whisk together all of the ingredients until well combined. Taste, and adjust ingredient amounts if desired.
For the BBQ jackfruit, heat 1/2 teaspoon olive oil in a medium-large nonstick skillet. Saute the jackfruit and peppers for 5 minutes over medium heat, stirring occasionally. Coat with the smoked paprika then cook for another minute. Reduce the heat to low, then fold in the beans. Cook for one minute, then stir in the BBQ sauce. Start with 1/4 cup sauce, adding more if you wish. Heat until warmed.
For the kale, remove the cooked sweet potato fom the baking sheet, then toss the kale in 1 teaspoon oil (or enough to lightly coat). Roast for 7 minutes, stirring once, or until crisped to your liking. Season with salt.
For assembly, split the cooked sweet potato in your serving bowl, then top with half of the tahini sauce and half of the kale. Spoon the BBQ jackfruit mixture on top (there may be some jackfruit/beans leftover depending on the size of your sweet potato and your appetite), followed by the remaining kale and sauce. Top with avocado, lemon, and toasted walnuts.
