In a Dutch oven, heat EVOO, 2 turns of the pot, over medium to medium-high heat, add butter to oil and when it foams, add onion, celery, and carrot, and cook, partially covered, 5-7 minutes to soften. Add garlic, stir, add ground meats and season with salt and finely ground black pepper. Break up the ground meats until they lose their pink color, then add bay, herbs, milk, season with a little freshly grated nutmeg and reduce heat to low simmer. Let milk absorb into meat completely, then add wine and let it absorb completely. Stir tomatoes into sauce, reduce heat to low, and simmer a few hours, low and slow.
Meanwhile, heat stock or water with a chunk of rind to simmer, reduce heat to low. When the sauce looks like it may be drying out, add a few ladles of the warm liquid to moisten it, keeping the bolognese at a low bubble. To serve, remove bay leaf and herb bundle. If need be, add water to your stock blend to keep the sauce at bubble for at least 3 hours.
Cook pasta in 6 quarts salted water about a minute, minute and a half less than the package directions. Reserve a half a mug full of starchy cooking water if you have used all of your stock or Parm-infused warm water. Drain pasta or remove from water with spider. Toss pasta with a few pats of butter and combine with sauce and a little stock or reserved water if necessary. Pass grated Parmigiano-Reggiano cheese at table.