- 3 tablespoon unsalted butter (plus more for casserole dish, divided)
- 2 cup grated sharp cheddar cheese
- ½ cup grated jack or Manchego cheese
- ½ cup grated pepper jack
- 5 tablespoon all-purpose flour
- 3 cup heavy cream
- 2 roasted poblanos (stemmed, halved, seeded and cut into ½‑inch dice)
- 2 teaspoon kosher salt
- 3/4 teaspoon freshly ground black pepper (plus more for boiling macaroni)
- 1 pound dried elbow macaroni
- ½ cup fine breadcrumbs
- 1 jalapeno (sliced with seeds)
Position a rack in the center of a convection oven and heat the oven to 400 degrees. Grease a 9 x 13 x 2‑inch casserole dish (or similar) with butter and set aside. In a medium bowl, combine the cheeses and set aside.
In a medium saucepan, over medium heat, melt 3 Tablespoons butter. Add in flour and whisk until combined. Cook, whisking constantly, until roux is smooth and thick, 1 to 2 minutes. Slowly add in 2 cups of the heavy cream, continuing to whisk and cook over medium heat until sauce begins to thicken, several minutes. Add ½ of the cheese mixture and stir until smooth. Add the remaining cream, diced poblanos, salt, and pepper. Keep warm over low heat.
Meanwhile, cook the macaroni in boiling salted water, just until al dente. Drain well and while paste is still hot, add it to the prepared casserole pan. Sprinkle pasta with ½ of the remaining cheese mixture and pour cheese sauce over pasta. Top with the last ½ of the remaining cheese and then cover evenly with breadcrumbs. Bake at 400 degrees for 10 minutes, then remove and top with sliced jalapeno. Bake for another 5 to 10 minutes or until sauce is bubbling and top is golden brown. Remove from oven and let sit a few minutes before serving.