Preheat oven to 450 degrees. Break up cream cheese in small batches in a food processor at low speed. Add salt and process at a pulse to combine. Add eggs, egg yolk, basil, sour cream, sugar, cornstarch, lemon juice and vanilla. Process until smooth.
Pour the batter into prepared crust. Bake the cheesecake until just set, about 35-40 minutes, being careful not to overcook. Remove pan and let cool on a wire rack for about an hour. Cover with plastic wrap and put in the refrigerator overnight (or at least 4 hours). Garnish with basil leaves. Serves 10 to 12.

