Preheat the oven to 400 degrees Fahrenheit.
Wash sweet potatoes and poke a few times with a fork. Place on a baking sheet. Drizzle with oil and use your hands to make sure each potato is evenly coated in oil. Bake for 45-55 minutes or until potatoes are easily pierced with a fork. Set aside.
While the potatoes bake, add the olive oil and onions and pepper to a non-stick skillet over medium-high heat. Sautés until onions are translucent. Stir in the taco seasoning and garlic and sauté for 1 minute.
Stir in the black beans, salsa, and ~1/4 teaspoon sea salt. Cook for 2-3 minutes. Taste and add more salt if needed. Set aside.
Add all of the avocado topping ingredients to a food processor and blend until smooth. It will be a little thick. If you prefer you can add more water (1 tablespoon at a time) to make it thinner.
To assemble, cut potatoes in half lengthwise and use fork to fluff insides. Top with 1/4 black bean filling and add a dollop of avocado topping. Garnish with sliced jalapeños, chopped red onion, and cilantro if desired.