Prepare ingredients: Dice the yellow onions, peel and dice the apples, mince the garlic, and chop the parsley. Grate the Parmesan cheese and set aside.

Cook sausage: In a Dutch oven, heat 2 tablespoons of olive oil over medium-high heat. Add Italian sausage and cook for 8–10 minutes until browned. Remove sausage and leave drippings.

Caramelize onions and apples: Add 4 tablespoons of unsalted butter, onions, apples, thyme, red pepper flakes, kosher salt, and black pepper. Cook for 25–30 minutes until onions are dark brown.

Cook pasta: In a large pot, bring salted water to a boil and add pasta. Cook for 8 minutes, then reserve 1 cup of pasta water and drain the rest.

Combine ingredients: Add minced garlic to caramelized mixture, cook for 1 minute. Pour in dry white wine, scrape bottom of pot and allow to evaporate for 4–7 minutes.

Finish pasta dish: Once the wine has reduced, add cooked orecchiette and reserved pasta water. Mix in cooked sausage, parsley, and half of the Parmesan cheese.