Cook your pasta according to packet instructions, so that is al dente. Make sure to reserve a cup of the pasta water. Drain the pasta in a colander.
Make your pesto if using a homemade recipe.
Combine the pesto and ricotta in your pot, along with 2 tablespoons of the pasta water. Stir to a cream sauce, adding more of the pasta water as needed. You can of course also spoon in more of either the pesto or cheese if you like more sauce. For a little kick of acid, add the (optional) apple cider vinegar.
Add the pasta back into the pot and stir well so it is coated in the sauce.
Use tongs to transfer the pasta to your serving bowl, and season with salt and black pepper. Add a few fresh basil leaves to garnish, then serve immediately.
