1 large ripe banana (firm, not overly soft)
1/2 small onion, thinly sliced
1 small tomato, chopped
1 garlic clove, minced
1/2 tsp curry powder
1/4 tsp turmeric powder
1/2 tsp mustard seeds
1 tbsp vegetable oil
Salt to taste
Fresh cilantro for garnish
Cooked rice or flatbread (optional, for serving)