Southwest Mac and Cheese with Cornbread Topping

4 poblano peppers
1 pound elbow macaroni
6 tablespoons unsalted butter
4 cups cornbread
1/4 cup all purpose-flour
4 cups whole milk
1/2 onion, finely diced
2 cloves garlic, minced
2 teaspoons oregano
12 ounces extra-sharp cheddar, grated
10 ounces Monterey jack, grated
1 seven ounce can diced green chile peppers
1 red bell pepper, finely diced
Salt to taste

Halve poblanos lengthwise and remove core, stem, seeds, and membranes. Coat with a little oil, place skin-side up on a greased baking sheet, and roast in a 450 degree oven until skin is blackened. Remove from oven and put into a paper bag to steam and cool for about 10 minutes. Remove from bag, peel skin off peppers, and dice.

Cook the macaroni according to package directions. When cooked and drained, toss with 2 Tbsp butter.

Grate the cornbread into crumbs (you can use a food processor for this step).

Preheat oven to 350 degrees and grease a large baking dish.

In a medium saucepan, melt the remaining 4 tablespoons of butter over medium-low heat. Sprinkle in the flour and whisk pretty constantly for 3 minutes. Whisk in the milk. Add the onion, garlic, and oregano. Simmer, whisking occasionally until it begins to thicken.

Stir in cheeses gradually, mixing to incorporate as cheese melts.

Stir macaroni and all peppers into the cheese sauce. Pour into the prepared pan. Top with cornbread crumbs (good in a thick layer).

Cover with tinfoil and bake for about 30 minutes, until it is bubbling around the sides. Remove the tinfoil and bake 10 more minutes until the cornbread crumbs are turning golden brown. Let stand 5-10 minutes before serving.

NOTES
From Serious Eats.
Not a hit with the kiddos, but the husband and I liked this quite a lot.