sweet potato and white bean stew with harissa and tahini (vegan)

Name: sweet potato and white bean stew with harissa and tahini (vegan)
Prep time: 5 min
Cook time: 25 min
Total time: 30 min
Cuisine: American
Ingredients: 1 yellow/sweet onion - finely diced; 4 cloves garlic - minced; 2 cups diced sweet potato - from one small sweet potato; 2 cups chopped green beans (can be frozen or fresh, I used fresh); 1 bunch parsley - finely chopped; 2 cans white beans - drained; 2 cups vegetable broth; 2 tbsp harissa paste; 1 ~18 oz jar crushed tomatoes; 1 tsp cumin; 1 tsp paprika; salt to taste; black pepper to taste; ½ tbsp soy sauce (can omit but add more salt); ½ tbsp maple syrup; 1 tbsp apple cider vinegar or another culinary vinegar; ¼ cup tahini (optional but adds creaminess)