Cultured Butter

Instructions

1. • 1 quart heavy cream 
   • 2 tablespoons buttermilk
   Combine cream and buttermilk in clean lidded container. Cover container or close carton and let sit at room temperature until mixture smells tangy and buttery and has a thick consistency, at least 24 hours or—our recommendation—up to 7 days. 
2. Chill cream to 55 to 60 degrees F/10 to 15.5 degrees C. 
3. Transfer cream to food processor and process until mixture turns from grainy whipped cream to lumps of butter splashing in liquid, 1 to 3 minutes. Stop processor immediately.  
4. Fill medium bowl halfway with ice and water. Line fine-mesh strainer with triple layer of cheesecloth, leaving few inches of cloth hanging over sides of strainer. Pour butter mixture through cheesecloth-lined strainer into large bowl (buttermilk will collect in bowl). Lift cheesecloth by edges and twist and squeeze tightly over strainer to press out more buttermilk (when butter starts to squeeze through cheesecloth, you are done). Transfer cheesecloth-wrapped butter to ice bath until firm around exterior, about 2 minutes. Transfer buttermilk to airtight container; do not wash bowl. 
5. • ¼ teaspoon salt (optional) 
   Remove butter from cheesecloth and transfer to now-empty bowl. Stir and press with wooden spoon to force out additional buttermilk from butter, 1 to 2 minutes. Drain this buttermilk from bowl, add to buttermilk container, and refrigerate until ready to use. If making salted butter, knead salt into butter with wooden spoon. Transfer butter to separate airtight container and refrigerate until ready to use. (Butter can be refrigerated for up to 2 months.)