Preheat oven to 400.
Peel and cut sweet potatoes in 1/2 inch cubes.
Toss sweet potatoes with 1 Tbsp olive oil and salt. Put on baking sheet.
Roast until tender - about 15 to 20 minutes.
Meanwhile heat 2 Tbsp oil in large pan over medium heat. Add onion and cook until softened 5-6 minutes.
Stir in garlic and black beans.
Add roasted sweet potatoes, honey, cumin, juice from two limes and cook until liquid is absorbed. Salt and pepper to taste.
Spread avocado crema onto warmed tortillas, top with sweet potato and black bean mixture.
Garnish with avocado slice and chopped cilantro.