Heat the olive oil in a large deep skillet over medium-high heat—wait until you see a thin haze of shimmer, about 2 minutes. Slice your chicken into 1/2-inch pieces, season with half the salt and black pepper, then place them in the hot pan without moving for 4 minutes. This sear is what keeps the chicken from tasting boiled; I learned this the hard way after years of stirring too early. Flip each piece and cook 3 more minutes until golden on both sides, then transfer to a clean plate.

In the same pan, add the butter and diced onion—don't wash the pan, those browned bits are flavor gold. Cook the onion over medium heat for 3 minutes, stirring occasionally, until it turns translucent. Add your minced garlic and cook for exactly 1 minute; any longer and it burns, which turns the whole dish bitter. I know this because I've done it, and there's no saving it once that happens. The kitchen should smell intensely garlicky right now—that's your signal you're on track.

Add the sliced mushrooms to the pan and stir to coat in oil and butter. Cook for 5 minutes without stirring too much; you want them to release their moisture and start browning on the cut sides. This is when the warm mushroom comfort flavor develops. Stir occasionally after the first 3 minutes. The mushrooms will shrink down and look dark and concentrated—that's exactly what you want. If you rushed this step or skipped it, your sauce will taste thin and watery.

Pour in the chicken broth and dried thyme and rosemary, then scrape the bottom of the pan with a wooden spoon to release all those caramelized bits. Add the dry pasta directly to the pan along with 1/4 teaspoon of the salt, and stir to break up any clumps. Bring the liquid to a boil, then reduce heat to medium and simmer uncovered for 18-20 minutes, stirring every 3 minutes so the pasta cooks evenly and doesn't stick to the bottom. The pasta should absorb most of the liquid and become al dente. This is the most important step for getting a creamy mushroom chicken pasta cozy recipe that tastes authentic—the pasta is cooking directly in the seasoned broth, not in plain water.

Return the chicken to the pan, then pour in the heavy cream and stir constantly for 1 minute to combine it with the pasta liquid. Add the shredded cheese in two handfuls, stirring gently after each one so it melts evenly. Taste and adjust salt and pepper to your preference—remember you already added some earlier, so go easy. The sauce should coat the back of a spoon when you dip it in; if it looks too thin, simmer for 1 more minute without the lid. If it looks too thick, add 2 tablespoons of cream and stir. The whole process from sear to plate takes 55 minutes, and almost none of that involves active work on your part.