Peel off the raw plantain and cut into roundels around 4-5mm in thickness. Add sambar powder, salt, turmeric powder and tamarind paste. Add 1 or 2 teaspoon of water if needed and rub the spices in. Let this marinate for 10-15 mins at the least.
Meanwhile, heat a thick bottomed flat pan or cast iron pan and add 1 tablespoon oil. As the oil becomes hot, reduce the flame to low and place the marinated plantain slices on the pan. Cook on each side for 4-5 mins.
Once the bottom looks crisp and golden, turn them around and cook on the other side too. Remove from the pan and repeat with the next batch.
Serve hot with rice, rasam/sambar or curd rice or any variety rice.