In a large skillet heat the oil. Add the medallions and saute them over high heat for 2 minutes a side to brown them. Lower the heat and continue to cook slowly for about 5 minutes or until just cooked through. Don't overcook or they will toughen. When done, remove the medallions to a serving plate.
To the remaining oil add the cumin, turmeric and tomatoes and stir for a few seconds just to heat the tomatoes; season to taste with salt and crushed red pepper and spoon over the medallions.