Fancy Manchego Mac and Cheese With Chorizo

extra virgin olive oil ( for drizzling )

1 / 2 lb chorizo sausage ( raw, casting dicarded, chopped )

3 tbsps butter

2 shallots ( chopped )

3 1 / 2 garlic cloves ( finely chopped )

3 tbsps flour

1 / 3 cup dry sherry

1 cup chicken broth

1 cup whole milk ( or 1 cup half-and-half )

2 cups manchego cheese ( shredded )

2 cups frozen peas

1 / 4 cup peppers

1 / 2 cup flat-leaf parsley ( coarsley chopped )