Mix chaat masala, red chili powder, paprika and salt. Store in an airtight container.
When you are ready to use the spice mix, grill the corn over a medium flame (for about 5-7 minutes), rotating until all sides are well charred.
Dip a wedge of lime in the spice mixture and rub the lime and spice mixture against the corn while applying enough pressure to squeeze out the lime juice. Repeat several times, in order to thoroughly coat all sides of corn. Enjoy Hot.