Before you start cooking – soak raw cashews in just boiled water in a heat proof bowl for at least 30 minutes, or up to an hour.
Bring a large pot of salted water to boil. Cook pasta according to package instructions, undercooking by about 1 minute (it will continue to cook a bit more in the sauce).
Heat olive oil in a large skillet over medium heat. Add smashed garlic cloves and cook, stirring frequently, until tender and lightly caramelized.