1 cup (8 fluid ounces) buttermilk
1 cup (225 g) sour cream
1 tablespoon white wine (or white balsamic) vinegar
1/2 teaspoon kosher salt
1/4 teaspoon freshly ground black pepper
1 tablespoon dried dill
2 tablespoons minced dried onion (or 1 tablespoon dried ground onion)
1/2 teaspoon garlic powder
1 pound raw skinless, boneless chicken breasts
12 ounces dried gluten free rotini pasta
3 ounces (about 3 strips) sliced bacon, diced
3 tablespoons (42 g) unsalted butter, chopped
5 tablespoons (45 g) basic gum-free gluten free flour blend (30 g superfine white rice flour + 10 g potato starch + 5 g tapioca starch/flour) (or replace with an equal amount of superfine sweet white rice flour)
1 1/2 cups (12 fluid ounces) chicken stock
8 ounces sharp yellow cheddar cheese, shredded
Chopped fresh flat-leaf parsley (optional)
Preheat your oven to 375°F. Grease a 3-quart casserole dish and set it aside. Line a large rimmed baking sheet with parchment paper and set it aside.
Make the ranch dressing and cook the chicken. In a medium-size bowl, place the buttermilk, sour cream, vinegar, salt, pepper, dill, onion and garlic powder, and whisk to combine well. This is the ranch dressing. Place the raw chicken breasts on the prepared baking sheet and spoon about 1/4 cup of the ranch dressing evenly on top of the chicken breasts. Place the chicken in the center of the preheated oven and bake until the chicken is opaque throughout and reaches 160°F on an instant-read thermometer (about 20 minutes). Remove the chicken from the oven and allow it to rest for about 5 minutes before cutting it into 1-inch square pieces. Lower the oven temperature to 350°F.
Boil the pasta. While the chicken is cooking, in a large pot of salted water, boil the pasta to an al dente texture according to the directions on the package. I used Barilla gluten free rotini pasta, and boiled it for 6 minutes. Drain the pasta, rinse it with lukewarm water and set it aside.
Cook the bacon and make the sauce. In a medium-size, heavy-bottom saucepan, cook the bacon over medium-high heat until browned and crispy. Remove the cooked bacon from the saucepan and transfer to a paper towel-lined plate to drain, and discard all but 1 tablespoon of the bacon grease. Place the unsalted butter in the pan, and melt over medium heat. Add the flour blend and cook, whisking constantly, until the mixture is bubbling (about 2 minutes). Add the chicken stock in a slow, steady stream, whisking constantly. Cook, whisking occasionally, until the mixture begins to thicken (about 2 minutes more). Add the remaining ranch dressing in a slow, steady stream, whisking constantly until well-combined. Remove the saucepan from the heat.
Assemble and bake the casserole. Add the cooked pasta, diced chicken and about 6 ounces of the shredded cheddar cheese to the saucepan and toss to combine. Transfer about half of the pasta and chicken mixture to the prepared casserole dish in an even layer, scatter with about half of the cooked bacon, top with the remaining chicken and pasta mixture, then the remaining bacon. Scatter the remaining shredded cheese evenly over the top. Place the dish in the 350°F oven and bake until the mixture is bubbling and the cheese is melted (about 10 minutes). Scatter with the optional chopped parsley and serve immediately.
Adapted from Damn Delicious.