Step 1Mix the cornstarch with 1/4 cup milk until smooth. Add 3/4 cup of milk and cook in the top of a double boiler set over, but not touching, simmering water until thick and smooth, about 10 minutes, beating constantly to avoid lumps.
Step 2Blend the sugar, eggs, salt and evaporated milk in an electric mixer. Add the hot cornstarch mixture and beat well. Add the whipping cream, remaining milk and vanilla extract.
Step 3Freeze in an ice cream maker according to manufacturer's instructions. You may have to do this in 2 batches.