2 tablespoons olive oil extra virgin extra-virgin divided
2 tablespoons parmesan grated
3 inch to 5 chilies fresh red such as serrano, thinly sliced, or 1/4 teaspoon hot red-pepper flakes
0.5 cup spring onion thinly sliced
2 tablespoons butter unsalted divided
Equipment
frying pan
pot
Directions
Cook fettuccine in a pasta pot of well-salted boiling water until al dente, about 3 minutes. Reserve 1 cup cooking water, then drain pasta.
While pasta water comes to a boil, cook spring onions in 1 tablespoon oil and 1 tablespoon butter in a 12-inch heavy skillet over medium heat, stirring occasionally, until softened, about 2 minutes.
Add 1/2 cup pasta-cooking water, peas, 1/4 teaspoon salt, and 1/8 teaspoon pepper and cook 1 minute.
Add crab and cook until heated through, about 2 minutes.
Add pasta, lemon juice, cheese, chile, and remaining tablespoon each of oil and butter and stir to combine well, adding more cooking water to moisten if necessary.
Remove from heat and stir in all but 1 tablespoon parsley.