Anchovy and Caper Butter with Spaghetti alla Chiatarra

1. Combine butter, anchovies and capers. Mix well. Form into a log and wrap in saran wrap.
2. Chill in the freezer until slightly firm, about 20 minutes.
3. When ready to serve, bring 5 quarts of salted water to a boil. Cook the pasta according to package instructions. Drain, reserving 1/2 cup of the pasta water.
4. Remove butter from the refrigerator and cut enough slices to coat pasta. (Depending on how buttery you’d like it, you can use ½ of log* or full log.) Add slices to large serving bowl.
5. Add pasta and pasta water. Toss to coat. Serve immediately.

*Compound butter can be made ahead of time and stored in the refrigerator for up to 1 month or in the freezer for 3 months.