- 3/4 cup peeled, seeded, and chopped Italian plum tomatoes (about 3)
- 2 teaspoons minced garlic
- 1/2 cup Shrimp Stock 
- 1/2 teaspoon salt
- 1 light pinch cayenne pepper
- 2 turns freshly ground black pepper
- 1 stick unsalted butter, cut up
- Mash the tomatoes with a whisk in a small nonreactive saucepan over high heat for about 1 minute. Add the garlic, Shrimp Stock, salt, cayenne, and black pepper and bring to a boil, whisking. Continue cooking, whisking constantly, for about 1 minute.
- Add the butter a few pats at a time, and when half incorporated, remove the pot from the heat and continue whisking until all of the butter is incorporated.
- Serve immediately or prepare only through Step 1; store, refrigerated, in airtight container. Reheat in a saucepan over low heat. When the sauce comes to a simmer, proceed with Step 2.