-
1
Set a heavy pot — cast iron or enamelled cast iron with a tight-fitting lid — over a medium-high flame. Add the olive oil and, when it shimmers, lay in the beef. Brown the piece on all sides until a deep mahogany crust forms on each face. Remove the meat and set aside. The crust must be thorough: pale meat at this stage will not give the onions enough depth to carry.
-
2
Reduce the heat to its absolute minimum. Add the carrot and celery to the pot and stir briefly. Pile in all the sliced onions — yellow, white, and red — in their full quantity. Lay the browned beef on top, pressing it down into the onion mass. Pour the white wine over everything. Cover the pot with its lid.
-
3
Cook, covered, on the lowest possible heat for 4 to 6 hours. Do not stir more than once every 30 to 45 minutes. In the first hour, the onions will release a great quantity of water and begin to soften. In the second and third hours, that liquid will reduce and the onions will begin to colour. If, at any check, the bottom shows signs of catching, add the smallest possible splash of water and scrape gently. No further liquid should be added. This is where the dish lives or dies: if the heat is too high the onions brown before they melt, and the sauce breaks into bitterness rather than sweetness; if the patience holds and the heat stays low, the onions dissolve entirely into a thick, amber-coloured cream of profound sweetness and savour.
-
4
After 4 to 6 hours, lift the lid and examine the contents. No individual onion slice should remain visible. The sauce must be a unified, deep golden-brown cream, glossy and thick, with no trace of watery liquid. The beef, when probed with a skewer or carving fork, should offer no resistance — it is fall-apart tender throughout.
-
5
Lift the beef from the sauce in one piece. Set it aside, covered, to rest. Taste the onion sauce and correct for salt. Bring a large pot of well-salted water to a rolling boil. Cook the broken ziti or candele until just al dente. Drain, reserving a ladleful of pasta water. Dress the pasta in the pot with several generous spoons of the onion sauce, loosening with a little pasta water if needed. The pasta must be deeply coated — amber, glossy, yielding — with no pale, undressed pieces.
-
6
Serve the dressed pasta as the first course. Slice the rested beef across the grain and present it, with the remaining onion sauce spooned over, as the separate second course.