Lisa LaValle, chef and manager of the Des Moines Art Center Restaurant, is leaving to create a new restaurant at the Greater Des Moines Botanical Garden, the Art Center announced yesterday. LaValle has been the chef at the Art Center for 20 years. David Baruthio, co-owner and chef of Baru 66 in Windsor Heights, will open a second location in the Art Center on Sept. 17, called "Baru 66 at the Art Center." Baru 66 is a French contemporary bistro, and the Art Center location will be open during lunch on weekdays and Saturdays.