For the pesto, combine basil, garlic and walnuts in a food processor with ¼ cup olive oil.

Pulse until you have a slightly chunky sauce, but not smooth.

Add the remaining oil and continue to process until smooth.

Stop once or twice to scrape down the sides.

Stir in the cheese and season with salt. Set aside.

Soak the onion rounds in milk for about 5 minutes.

Heat oil in a large skillet.

Take onions from the milk and place in the flour, mix to coat evenly.

Fry the onions in batches until crispy and evenly browned.

Drain on paper towels. Set aside.

In a large pot of salted boiling water, cook pasta to al dente.

When finished, drain pasta, reserving a cup of pasta water.

In a large bowl, combine the pasta with pesto and a splash or two of the pasta water (should the sauce need to be thinned a little).

Finish with a hefty sprinkle of grated Parmesan and crispy onions.