Three-Cheese Baked Mac and Cheese with Buttery Herb Crumbs

Preheat the oven to 375°F (190°C) and butter a 9x13-inch baking dish.

Bring a large pot of well-salted water to a rolling boil, add the elbow macaroni, and cook 2 minutes shy of package directions until just shy of al dente; drain and toss with a drizzle of olive oil.

In a heavy saucepan, melt 4 tbsp of the butter over medium heat until it foams, then whisk in the flour and cook 1-2 minutes until it smells nutty and looks pale golden.

Gradually whisk in the warm milk, a splash at a time, letting each addition emulsify before adding more; simmer 5-7 minutes until the sauce thickly coats the back of a spoon.

Off the heat, whisk in the Dijon, garlic powder, nutmeg, 1 tsp salt, and several grinds of black pepper, then stir in the cheddar and gruyère by the handful until glossy and smooth.

Fold the pasta into the sauce along with the parmesan; taste and adjust seasoning, then transfer to the prepared dish.

Melt the remaining 2 tbsp butter, toss with panko, thyme, and a pinch of salt until evenly coated, and scatter over the top.

Bake 22-25 minutes until the edges bubble furiously and the crumbs turn deep golden; rest 5 minutes before serving.