Bring a large pot of salted water to a boil. Add the orecchiette then cook for 9-12 minutes or until al dente. Reserve 1 cup of cooking water and drain.
While the pasta cooks, start the sauce. Lay the shucked corn on its side and with a sharp knife, slice off the kernels.
In a large pan, saute the red onion in a splash of oil until soft and translucent.
Add the garlic, lemon zest and chilli flakes and cook for 30 seconds. Add the corn kernels (I always keep some to top the finished pasta with but this is optional) and cook for a few minutes, stirring regularly.
Pour in the cream and sour cream then season with salt and pepper and add the lemon juice. Allow to simmer for 5 minutes until the sauce coats the back of a spoon easily.
Stir the sauce and basil pesto through the cooked pasta, adding some of the pasta cooking water to loosen the sauce.
You want the pasta to be super creamy but not watery.
Serve in bowls topped with more basil pesto and fresh basil leaves.