Bring a large pot of salted water to a boil and cook the pasta until al dente. Reserve ½ cup of the pasta water, then drain the pasta.
Add the cottage cheese, Parmesan, milk, garlic, Italian seasoning, salt, and black pepper to a blender. Blend until completely smooth.
Melt the butter in a large skillet over medium-low heat.
Pour the blended sauce into the skillet and cook for 2-3 minutes, stirring frequently. Do not let it boil.
Add the cooked pasta and toss until evenly coated.
Add a splash of the reserved pasta water until the sauce reaches your desired consistency.
Garnish with parsley, extra Parmesan, and red pepper flakes before serving.