Start your grill and set the knobs to medium-high. Alternatively, you can use a grill pan on the stove over medium heat, although your cooking time may vary.
Shuck the ears of corn. Place them on the grill. Turn about 1/8 to 1/4 turn after about 1 1/2 minutes. Continue to do the same until the corn has been turned completely. This takes about 8-10 minutes for the corn to cook. You should have some charred parts.
Remove the corn and set aside to cool.
While the corn is cooling, mix the ingredients for the sauce in a small bowl - mayonnaise, sour cream, lime juice, cumin, onion powder, garlic powder, chili powder, salt, and pepper.
Cut the corn kernels off the cobs and put them in a mixing bowl.
Add the red onion, chopped cilantro, and the sauce you just mixed. Stir to blend well.
For best results, refrigerate for 1 hour before serving, although you can serve the salad immediately.
Top with queso fresco, paprika, torn cilantro, and lime wedges.