Press the sauté button, then add the oil and allow it a minute to heat up. Add the mustard seeds and once they begin to pop, add the garlic, ginger, spices and stir, then add the tomato sauce, yogurt and water. Mix well.
Place a steamer rack on top of the sauce, then place the corn on the cobs on top of the rack.
Secure the lid, close the pressure valve and cook for 3 minutes at high pressure.
Open the valve to quick release any remaining pressure.
Using tongs, remove the corn on the cobs and once cool to touch, cut the kernels off the cob. Place the freshly cut corn pieces back into the pot along with the dried fenugreek leaves. Mix well and serve.