To make the ragù, in a large Dutch oven over medium-low, combine the oil, the carrots, celery, onion, 1 teaspoon salt and ½ teaspoon pepper. Cook, stirring often, until the vegetables are fully softened but not browned, 25 to 30 minutes.

Increase to medium, then add the beef, pork, coriander, fennel, cinnamon and nutmeg; cook, stirring occasionally and breaking the meat into small pieces, until the meat is no longer pink, 4 to 6 minutes. Add the tomato paste and garlic; cook, stirring, until the tomato paste darkens slightly, 1 to 2 minutes. Add the wine and cook, scraping up any browned bits, until almost fully evaporated, about 2 minutes. Add 3 cups water and the bay, then bring to a simmer over medium-high. Reduce to medium-low and cook, uncovered and stirring occasionally, until the meat is tender and the liquid has reduced by about half, 30 to 35 minutes.

Meanwhile, make the besciamella. In a small saucepan over medium, melt the butter. Whisk in the flour and cook, whisking constantly, for 2 minutes. While whisking, gradually add the half-and-half, then bring to a simmer. Cook, whisking often, until the sauce thickens and no longer tastes of raw starch, 3 to 4 minutes. Off heat, stir in the Parmesan; set aside until ready to use.

About 20 minutes into simmering the ragù, cook the pasta. In a large pot, bring 4 quarts water to a boil. Add the penne and 2 tablespoons salt, then cook, stirring occasionally, until the pasta is somewhat softened but still very firm at the core (begin testing about 5 minutes before the recommended cooking time on the package). Drain the pasta in a colander.

When the ragù is ready, remove and discard the bay, then add the besciamella; cook over medium-low, stirring, until the mixture is slightly thickened, about 2 minutes. Gradually add the pasta, stirring to coat and break up clumps. Cook, stirring and “dragging” the pasta through the sauce, until the pasta is al dente, 2 to 3 minutes. Off heat, taste and season with salt and pepper. Serve sprinkled with Parmesan.