This sauce of “melted” onions has the flavor profile of a rich French onion soup. I have had many versions of this, ranging from a quick, barely cooked sauce of sautéed onions to a luscious, deeply flavored sauce that gains complexity from slow cooking. Marrow bones are available in some butcher shops. If you can’t find them, omit them, but the result won’t be quite as richly delicious. If you substitute beef consommé for the Brodo di Carne, reduce the salt to 1 Tbsp.
SERVES 6
6 TBSP [84 G] STRUTTO
THREE 3 IN [7.5 CM] LONG MARROW BONES, CUT CROSSWISE
8 OZ [227 G] PANCETTA, FINELY DICED
21/2 LB [1.1 KG] SHALLOTS, PEELED AND THINLY SLICED
10 LARGE YELLOW ONIONS, THINLY SLICED
2 TBSP KOSHER SALT, PLUS MORE FOR SEASONING
1 TBSP FRESHLY GROUND BLACK PEPPER
2 CUPS [480 ML] DRY WHITE WINE
3 CUPS [480 ML] BRODO DI CARNE (PAGE 237), OR BEEF CONSOMMÉ
1 RECIPE TAGLIATELLE (PAGE 88)
1 CUP [100 G] FINELY GRATED PARMIGIANO-REGGIANO
In a large heavy-bottomed pot over medium heat, melt the strutto. Add the bones and cook on all sides until golden brown and the marrow begins to weep out, about 6 minutes total.
Decrease the heat to low. Carefully shake the marrow from the bones into the pot. It should be loose and come out easily. If it resists, use the end of a spoon to push it out. Discard the bones. Add the pancetta and cook, stirring occasionally, until crispy and golden brown and the fat has rendered, about 5 minutes. Add the shallots, onions, salt, and pepper and stir to combine.
Increase the heat to medium and cover the pot. Cook until the shallots and onions are very soft and golden, about 1 hour, stirring every 10 minutes. If the onions stick to the bottom of the pot, remove the pot from the heat and let sit, still covered, for 3 to 5 minutes. The onions will naturally release from the pot. Stir, scraping the bottom of the pot, and return it to the heat.
Increase the heat to high and uncover the pot. Cook until the onions are juicy and jammy and browned, 30 to 45 minutes. Add the wine and cook until the alcohol aroma dissipates and the liquid has reduced by half, about 6 minutes. Add the brodo and cook, stirring frequently, until the onions are once again juicy and jammy and the liquid has reduced by one fourth, about 15 minutes. Set the sauce aside.
Bring a large pot of water to a rolling boil over high heat. Season the water with salt (see page 25). When the salt dissolves, add the tagliatelle and cook until tender, 30 seconds to 1 minute.
Meanwhile, return the sauce to medium heat. Using a slotted pasta fork, transfer the pasta to the sauce and toss to coat. Add a splash of pasta cooking water to the pan and swirl vigorously to emulsify. Add 1/4 cup [25 g] of the Parmigiano-Reggiano and toss the pasta again. Serve immediately with the remaining Parmigiano-Reggiano sprinkled on top.
The sauce will keep, refrigerated in an airtight container, for up to 5 days.
