My first crack at this iconic treat was revealed in a copycat recipe I published 25 years ago that called for mixing milk with Nestle Quik and vanilla ice cream in a blender. Tasty? Sure, it was. But the finished product was too runny, and the flavor wasn't perfect. That's why I recently holed myself up in the lab and created a formula that you churn in a home ice cream maker until thick and creamy, and it now tastes just like the real thing.