Melt butter in a large skillet on the stovetop over medium heat. Add extra-virgin olive oil, stirring, until butter foam subsides. Add panko and garlic cloves, cook, stirring, until crumbs are golden brown, 4–6 minutes. Transfer crumbs to a medium bowl, stir in Parmesan and kosher salt set aside

Macaroni and sauce

Bring a large pot of salted water, covered, to a boil over high heat. Add dried elbow macaroni and cook, uncovered, until just al dente (avoid overcooking). Drain par-cooked macaroni and set aside (do not rinse).Place rack in the middle of oven; preheat oven to 400°F. Grease a 13x9” baking dish with unsalted butter. Melt unsalted butter in a large wide pot over medium-low heat. Sprinkle all-purpose flour over butter, whisking to incorporate, and make a roux. Cook, stirring constantly with a wooden spoon, until roux is light golden, about 4 minutes. Gradually pour in whole milk and heavy cream, whisking constantly to incorporate and make a béchamel sauce. Raise heat to medium-high and bring sauce to a low boil, whisking constantly. Reduce to a simmer, whisking occasionally, and cook until béchamel sauce is thick and coats the back of a spoon, about 3 minutes more. Add ground white pepper, mustard powder, and kosher salt. Add grated extra-sharp cheddar cheese and grated Parmesan in three batches, whisking until each addition is melted before adding more. Remove from heat. Add drained macaroni to pot with cheese sauce and stir well to coat. Transfer macaroni mixture prepared baking dish and place on a rimmed baking sheet (this is if the cheese bubbles over). Sprinkle panko topping evenly over macaroni and bake until golden and bubbling, 18–22 minutes. Let baked mac and cheese cool 15 minutes before serving.