1 Tbsp olive oil; 1 white onion diced; 3 cloves minced garlic; 2 Tbsp grated ginger; 2 pounds sweet potatoes peeled, cut into small pieces; 4 cups vegetable broth; 1/2 tsp salt; 1/4 tsp pepper; 1 cup shredded cheddar cheese; 2 Tbsp sliced green onions or chives. Place a large pot on the stove over medium high heat. Add in olive oil and onion and sauté until tender, about 7 min. Add in garlic and ginger and sauté 1 min more. Add in sweet potatoes and season with salt and pepper. Pour in vegetable broth and bring to a boil over high heat. Once boiling, reduce heat and simmer until tender. Transfer soup to blender and blend until smooth. Return to a pot over low heat and add in cheese. Serve topped with green onions or chives.