You don’t need a herd of dairy cows to make cheese, it turns out—just some fresh local milk and old-fashioned know-how. The latter may be obtained on August 21, when the founders of Brooklyn-based Salvatore Bklyn host a ricotta-making demo at the Whole Foods Market Bowery’s Culinary Center. The class costs $25, and preregistration is available at 866-462-2838. 95 E. Houston St., at Bowery.