Japanese Sweet Potato and Black Bean Curry (vegan)

Name: Japanese Sweet Potato and Black Bean Curry (vegan)
Prep time: 5 min
Cook time: 30 min
Total time: 35 min
Cuisine: Asian, Japanese
Ingredients: 1 small onion - finely chopped; 4 garlic cloves - minced; 2 bell peppers - finely sliced; 1 tsp cumin seeds; 1 tsp mustard seeds; 1 tsp turmeric; 1 small japanese sweet potato - cubed (can sub regular sweet potato); 1 bunch parsley or cilantro - finely chopped; 1 jalapeno - finely chopped with seeds removed; 2 tbsp red curry paste; 2 cans black beans; 1 24 ounce can crushed tomatoes; juice from 1 lime; 1 tbsp maple syrup or honey; 1 tbsp vinegar (I used rice wine vinegar); 1 tbsp soy sauce (can sub salt to taste); 1 can full fat coconut milk; black pepper to taste; cooked grain of choice (I used quinoa)