Peel the mango, then cut into bite-sized pieces, as well as the bell pepper. Cut the celery into small pieces and the spring onions into thin slices.
For the dressing, mix together vinegar, oil, maple syrup, chili powder, salt and pepper. Mix all ingredients in a bowl. It is best to let the salad sit for about 30 minutes.
If you want, you can use honey instead of the maple syrup, but then the salad is no longer vegan.