Preheat the oven to 400 degrees F.

Slice off the kernels from the ears of corn.

On a sheet pan, toss the corn and tomatoes with 1 tablespoon olive oil, 1/2 teaspoon kosher salt and 1/2 teaspoon black pepper. Spread the corn and tomatoes in a single layer with the tomatoes cut side up. Roast for 25-30 minutes until the corn is golden yellow and the tomatoes are wrinkled but still juicy.

For the pesto, put 1 cup roasted corn in a food processor with 1/3 cup olive oil, garlic, Parmesan, walnuts, 1/2 teaspoon kosher salt and 1/2 teaspoon black pepper. Puree the mixture until the pesto is fully combined into a sauce. (You will still see some corn kernels.)

Cook the pasta until al dente according to package instructions. Drain the pasta and transfer it to a large bowl. Stir in the pesto.

Fold the remaining corn, tomatoes and scallions into the pasta.