Lasagna

Method

1. sweat12 min
   medium-low, covered
   olive oil + onion + carrot + celery, until the vegetables go translucent and give up water without taking color — browning the soffritto here makes the finished ragù taste roasted rather than sweet
2. sear10 min
   medium-high, spread thin
   + beef + pork, broken up and left alone in a single layer until the bottom crusts; crowding the pan steams the meat gray and you lose the browning that carries the whole sauce
3. deglaze4 min
   high, until nearly dry
   + garlic + white wine, scraping the fond loose — the alcohol dissolves flavor compounds that neither fat nor water will pick up, then boils off
4. simmer15 min
   low, uncovered
   + 1 cup milk, until absorbed and barely any liquid remains. Milk goes in before the tomato on purpose: in acid the meat proteins tighten and stop tenderizing, so the dairy has to do its work first or the ragù stays grainy
5. stew105 min
   barest simmer, lid ajar
   + tomato paste cooked one minute to lose its tinny edge + crushed tomato + bay leaf + 1 tsp salt + black pepper, until the fat separates orange at the surface and the sauce mounds on a spoon. Two hours is not for flavor, it is for collagen: below a rolling boil it converts to gelatin, which is what makes the sauce cling to the sheets instead of running out of the slice
6. whisk8 min
   medium, constant motion
   butter melted + flour cooked 2 minutes to a pale paste, then 0.5 cup milk added in stages + nutmeg + remaining salt, until it coats a spoon thinly. Keep it looser than you think right — the dry sheets will drink it, and a stiff béchamel bakes into a rubbery seam
7. cook10 min
   assembly
   thin smear of ragù in the dish, then sheets + ragù + béchamel + parmesan, repeated for five layers, ending with béchamel and cheese so the top browns instead of curling. No boiling the sheets if the sauce is loose; they hydrate from the sauce and stay firmer for it
8. bake50 min
   190°C / 375°F, covered 30 min then uncovered
   covered first so trapped steam finishes the pasta, then uncovered so the surface dries and blisters. If it goes in naked the top sheets curl and go to leather before the middle is hot
9. rest25 min
   out of the oven, uncovered
   the layers are held together by gelatin and gelatinized starch, both of which are fluid at 90°C and firm at 60°C — cut it hot and it slumps into a bowl of sauce, cut it warm and the layers stand