Fresh Corn:  Remove husk and silk and trim corn. Add to a stock pot, cover with water and add ½ stick of butter. Cook for 15 minutes.  Allow to cool to touch and remove kernels from the cob.  

Heat a wide skillet over medium to high heat.  Add about two tablespoons of olive oil (twice around the pan).   Add corn kernels and cook for  10 -15 minutes, stirring infrequently so they get a golden char in some spots.   Add salt and pepper to the corn and mix to combine. 

Note:  Depending on the color you wish to attain, you may need to allow more time to get a "charred" look.  It will also take longer if using frozen corn.  

While the corn is cooking, mix together the mayonnaise, sour cream, chili powder, lime zest and juice in a Pyrex glass measuring cup.    

Note:  Add a few dashes of hot sauce to the dressing if you prefer more heat.  

When the corn is done, turn off the heat.  Add the dressing and cheese to the corn and toss to coat the corn evenly.  Fold in the queso fresco cheese and cilantro.  

Serve in a big bowl or individual bowls and garnish with extra cheese, cilantro and lime slices/wedges.