Bring a large pot of water to a boil with a large pinch of salt. Cut the corn kernels off the cob. Thinly slice the scallions and mushrooms. Mince or grate the garlic. Core, seed, and remove white veins from bell pepper, then thinly slice. HINT: Runaway corn kernels? Lay a large sheet of parchment paper or foil over your cutting board to gather the loose kernels that you've sliced.

Place a large bowl with ice water next to the stove. Add the soba noodles to the boiling water. Cook for 3-4 minutes, until al dente. Drain, reserving 1/4 cup of cooking water, then place the noodles in the ice water to stop the cooking. Set aside in the ice water.

Heat 1 table spoon olive oil in a large non-stick pan over medium heat. Add the bell pepper and mushroom and season with salt and pepper. Cook, tossing, for about 5 minutes, until softened. Add the garlic, scallions, and corn. Cook, tossing, about 2 minutes, until mushrooms are very soft and belll peppers are crisp-tender.

Drain the soba noodles and add them to the pan along with the sour cream and reserved pasta water. Toss to combine and cool for a minute or two until sauce has thickened and soba noodles are warmed through. Toss with half the parmesan cheese. Taste and season with salt and pepper.

Serve the soba noodles with a sprinkle of the remaining parmesan cheese on top.