Bring a large pot of salted water to a boil. Cook the pasta according to the package directions; drain. Return the pasta to the pot and toss with 2 tbsp. EVOO.
While the pasta is cooking, heat a large cast-iron or other heavy skillet over medium-high. Slice the kernels from the cobs and cook in the dry skillet, stirring occasionally, until browned in spots, about 4 minutes. Reduce the heat to medium and add the onion, garlic and 2 tbsp. EVOO. Cook, stirring occasionally, until the onion softens, about 2 minutes; season with salt and pepper.
Toss the pasta with the corn mixture. Divide among plates and top with ricotta and basil. Drizzle with EVOO and season.