When tomatoes are in season, I like to make this rich, all-purpose sauce and store it in the freezer for future use. When good, local tomatoes aren’t available, this recipe is almost as good using canned tomatoes. San Marzano tomatoes, an heirloom variety that’s favored for their big, sweet flavor and meaty texture, are the best canned variety. Cans labeled “DOP” (Protected Designation of Origin) come only from the San Marzano region in Italy, and while costly, they yield incredible sauce. But the term “San Marzano” is also used to refer to tomatoes not necessarily grown in Italy. These tomatoes are usually quite tasty, and cheaper.