700g boneless, skinless chicken breasts
200g sliced mushrooms
Coarse salt and freshly ground black pepper, to taste
Olive oil
30g unsalted butter
1 small white onion, chopped finely
1L chicken broth, preferably low-sodium
500g penne rigate
375ml heavy (whipping) cream, warmed
50g freshly grated Parmesan, plus more for serving
Cut the chicken breasts into 1-inch pieces. Season with salt and pepper. Brown the chicken in olive oil, in batches if necessary, and sauté until nicely browned on the outside, but still a bit pink inside, about 4 minutes (the pieces don’t have to be browned on all sides; two sides is fine). Remove the chicken and set aside on a plate.
Melt butter in a bit more olive oil and sauté the mushrooms for a few minutes, until browned. Remove the mushrooms and set aside with the chicken. Add the onion to the pan and sauté over medium heat until translucent, 30 seconds. Turn the heat to high, add the chicken broth to deglaze the pan. Bring to a simmer, lower to medium heat, and simmer for 5 minutes. Add the pasta, stir well, and simmer until the pasta starts to soften, about 8 minutes.
Stir in the warm cream and the browned chicken and mushrooms with any juices that have accumulated on the plate. Cover and simmer, stirring occasionally, until the pasta is tender, most of the liquid has been absorbed, and the chicken is cooked through, about 4 minutes more.
Stir in the parmesan until well incorporated, taste, and adjust the seasonings if needed.