Soft and Rich Vanilla Frozen Custard

"[Photograph: Robyn Lee] This recipe makes rich, soft frozen custard like you'll find at Shake Shack, Kopp's, Culver's, and all sorts of custard shops around the South and Midwest. For the softest, creamiest results, eat the custard within two hours of churning. This recipe can be easily doubled, but take caution to only make as much custard as you'll serve in one sitting. Why this recipe works: * High amounts of cream and egg yolks make the custard base full-bodied and super-creamy. * A small amount of corn syrup adds extra density and richness to the custard, replicating the texture professional custard machines provide. * Serving the custard right away mimics the "fresh from the machine" lightness of store-bought frozen custard...."