Every Thursday:  The Kona Historical Society’s Portuguese Stone Oven.  See this reproduction of a typical oven used by the Portuguese immigrants who came to Kona in the 1880s.  Join the process of panning bread dough and baking close to 100 loaves every Thursday. The program is free and the bread is available after 12:30 p.m. for $8 per loaf.  Bring your lunch and make a day of it with an oven-side picnic in the pasture. H.N. Greenwell Store Museum, Kealakekua. 10…