Method

• 1.
  Heat the oil and garlic in a saucepan over medium heat for 1-2 minutes until fragrant and garlic begins to turn golden (take care not to burn the garlic). Add the tomatoes, chilli flakes, onion half, butter and 1 tsp sea salt. Bring to a simmer, then reduce heat to low and cook, stirring occasionally, for 25-30 minutes. Splash in some water if it starts to stick or is reducing too much. Remove and discard the onion, then taste the sugo for seasoning. You may want to add a pinch of sugar, depending on the acidity of the tomatoes.
• 2.
  When the sugo has been simmering for 15 minutes, bring a large saucepan of well-salted water to the boil and cook the fettucine until al dente (9-10 minutes or according to packet instructions).
• 3.
  Reserve 1 cup (250ml) of the starchy cooking water and, using tongs, transfer the fettuccine to the tomato sauce and stir in spoonfuls of the reserved cooking water until the fettuccine is coated in the sauce. Taste again for seasoning, bearing in mind the feta will add saltiness.
• 4.
  Divide the pasta between plates, then finely grate the feta over to finish.