Pat the chicken dry and toss with the Italian seasoning, salt, and pepper. Heat the olive oil in a large deep skillet over medium-high heat. Add the chicken in a single layer and cook, turning once, until golden and cooked through, about 5–6 minutes. Transfer to a plate — it will go back in later.

Reduce the heat to medium. Add 1 tablespoon of the butter to the same skillet; when it foams, add the garlic and cook 30–60 seconds, until fragrant but not browned.

Pour in the chicken broth and water, scraping up the browned bits from the bottom. Bring to a boil, add the chickpea fettuccine, and stir well so nothing sticks. Reduce to a lively simmer and cook, stirring occasionally, until the pasta is al dente and most of the liquid is absorbed, about 8–9 minutes.

While the pasta cooks, blend the cottage cheese in a blender or food processor until completely smooth, 30–45 seconds. Scrape down once and blend again if any curds remain.

Reduce the heat to low. Stir in the blended cottage cheese, the remaining 2 tablespoons butter, and the parmesan until the sauce is smooth and glossy. Return the chicken (and any juices) to the skillet and fold in the spinach, if using, until just wilted, 1–2 minutes. If the sauce is thicker than you like, splash in 2–3 tablespoons of warm water.

Taste and season with more salt and pepper. Shower with parsley, parmesan, and red pepper flakes if you like, and serve straight from the skillet.