Spaghetti Aglio e Olio

No two ario e olio recipes are the same, but this one is pretty true to the classic method. The key is to slowly roast the garlic slices in olive oil until golden brown. If it is too thin, the flavor will not come out sufficiently, and if it is too thick, it will be bitter. my advice?
Ingredients
1 pound uncooked spaghetti

½ cup olive oil

6 cloves garlic, thinly sliced

¼ teaspoon red pepper flakes, or to taste

salt and freshly ground black pepper to taste

¼ cup chopped fresh Italian parsley

1 cup finely grated Parmigiano-Reggiano cheese