Lemon And Walnut Spaghetti

Directions

1. 1
   Bring a large pot of salted water to a boil.
2. 2
   Zest 2 of the lemons and set aside.
3. 3
   cut of the tops and bottoms off the other 2 lemons and cut lengthwise into quarters.
4. 4
   remove all seeds
5. 5
   Thinly slice the quarters crosswise into triangles.
6. 6
   Blanch the lemon pieces in the boiling water for 2 minutes, then transfer with a slotted spoon to a dish towel. Blot dry.
7. 7
   In the boiling water, add pasta and cook until just barely al dente. Drain, reserving 1/2 cup of the pasta cooking water.
8. 8
   Meanwhile, in a large pan, heat 1 tablespoon of the oil over high heat. Add the dried lemon pieces and season with a pinch each of salt and sugar. Cook until the lemons are caramelized and browned at the edges, 3 to 5 minutes. Transfer to a plate.
9. 9
   Melt the butter with the remaining oil in the pan over medium heat. Add the chile flakes and zest of both lemons; cook until fragrant. Whisk in the reserved pasta water.
10. 10
    Toss in pasta, juice of 1 lemon, cheese, pepper and the remaining salt. Cook until pasta is well coated with sauce. Toss in the caramelized lemon and parsley.