RECIPE FOR SUCCESS, the Houston-based nonprofit founded by Gracie Cavnar, has become known for its annual Delicious Alchemy banquet dinner. This year, the feast was a more intimate gathering at Hope Farms, hosted on a crisp fall evening instead of the usual late-spring date. But what didn’t change: The tradition of serving course after course of delectable treats, prepared by some of Houston’s best chefs, often utilizing produce from the farm.