Step 1

In a pot of salted boiling water, cook spaghetti until just shy of al dente (about 1 minute less than the package directs). Reserve pasta cooking water.

Step 2

Meanwhile, in a large skillet, combine 6 tablespoons oil and garlic. Add pinch of red pepper flakes, if using. Cook over medium heat until garlic is very lightly golden, about 5 minutes. (Adjust heat as necessary to keep it gently sizzling.)

Step 3

Transfer pasta to skillet along with 1/2 cup pasta water, increase heat to high, and cook, stirring and tossing rapidly, until a creamy, emulsified sauce forms and coats the noodles. Remove from heat, add remaining 2 tablespoons olive oil, and stir well to combine. Mix in parsley, if using, and serve right away.