Chop the walnuts roughly and toast them in a cast iron skillet on medium heat. Do this by working them around the pan for 2-3 minutes. You can also spread them on a baking sheet and toast at 425F for 3-4 minutes. Remove them from the heat when they are golden brown and fragrant.
Use a knife to remove the corn kernels from the cob. Set them to the side.
Finely dice the jalapeños, removing the seeds. And slice the scallions thinly, stopping when the pieces are mostly white.
Roll up each individual basil leaf and chiffonade the herbs.
In a large bowl, toss together the corn, jalapeño, scallions, basil and walnuts. Toss together.
Add a generous squeeze of lemon juice and a large glug of olive oil. Add pepper to taste and toss the salad again.
Use a microplane to finely grate the parmesan on top of the salad. Toss and add salt and pepper to taste again.
If you have any remaining, top with more parmesan cheese and serve!