In a medium-size bowl mix together the cauliflower, cheese, flour, yogurt, garam masala, and salt. Put a large nonstick skillet over medium-high heat and add the oil. Roll the cauliflower mixture into balls about the size of golf balls and begin to place them in the heated oil. Fry on all sides, in batches, 2 to 3 minutes, or until golden brown. Serve the koftas with the Sweet Potato Raita.
To make the raita: Put sweet potatoes in a small saucepot and cover with water. Boil until tender, approximately 10 minutes and then drain and cool. Put the sour cream and milk into a bowl and whisk until smooth. Add the onion, chives, garam masala, and salt and whisk well. Fold in the cooled sweet potatoes. Cook' s Note: Diced cucumbers can be substituted for the sweet potatoes.