Microwave the corn in their husks (two at a time) for 4 to 6 minutes, depending on their size (larger corn will take longer). Slice off enough of the stem end to expose the kernels, then push the corn out of the husk. (It will be hot; use a kitchen towel if needed). Repeat with the remaining two corn cobs. Slice the corn off the cob.
Melt the butter in a large saucepan set over medium heat. Add the corn kernels, scallions, garlic, 1/2 teaspoon salt, and several grinds black pepper. Cook, stirring, until the corn has softened and is beginning to brown, 5 to 6 minutes. Let cool for 10 minutes. (This will prevent the cottage cheese from separating).
While the corn is cooking, bring a large pot of salted water to a boil. Add the pasta and cook until al dente, according to package instructions. Reserve 1 1/2 cups of pasta cooking water. Drain.
Add the Parmesan and cottage cheese to the corn mixture. Use an immersion blender to blend until smooth, adding the reserved pasta water to thin it out as needed. (Alternatively, transfer the corn mixture to a blender and blend everything in there, then return to the pot).
Stir in the lemon zest and red pepper flakes. Add the cooked pasta and stir to coat. Taste and season with more salt as needed. (At this point, if you need to warm it up, do so over low heat).
Garnish with more thinly sliced scallions, if desired, and serve immediately.
