You can make it befor. Only put 1/2 the dressing on, add the remaining befor you serve .don't add cheese until the last minute. Cook corn just a few minutes then put in cold water to stop cooking. Nothing worse that overcooked corn.
I microwaved a couple large ears of corn & cut off the kernels. Subbed parsley for the cilantro (because I don't like cilantro) and subbed sweet onion for the radish (because that's what I had). Two colors of cherry tomatoes--pretty. Super easy & I'm really looking forward to lunch the next couple of days!