In a heavy saucepan add the cream, milk, sugar, salt. Stir to combine.

With a sharp knife, split the vanilla bean in half lengthwise. With the back edge of the knife, scrape the inside of each half to release the vanilla bean seeds (sometimes referred to as vanilla bean caviar). Add the vanilla bean seeds and the vanilla bean pod halves to the cream mixture.

Place pot over medium low or medium heat, stirring just until steam starts to rise. Do not boil.

Remove pot from heat and proceed with step #4.

In a medium size bowl, whisk together the egg yolks. Temper the egg yolks by slowly pouring about 1 cup of the hot cream mixture into the egg yolks while whisking quickly and constantly. Whisking is important because the hot liquid can cook the egg yolks, which would ruin the custard. Although this may sound like an intimidating step, it will work out very well if you remember to slowly add the hot liquid to the egg yolks while whisking quickly.

Pour the tempered egg yolk/cream mixture slowly back into the saucepan while again whisking quickly.

Over medium heat to medium low heat, continue to stir the mixture until it is thickened and coats the back of a metal spoon. Slide your finger across the back of the coated spoon. If a definitive line remains, then the custard is done. If not, continue to cook and stir the mixture, testing periodically with the spoon until the custard has developed.

Now this is an optional step, but it may be a good idea if you have noticed any small lumps in your custard base. Pour the custard through a fine mesh strainer into a separate bowl to separate out any of the little lumpy stuff.

Stir in the vanilla extract.

Place the pot or bowl with the custard into an ice bath and stir until the mixture has cooled. (I set the pot in a large bowl about a quarter filled with ice and a little water. Use whatever you have available, even the kitchen sink with some ice in it will do the trick.) REMOVE the vanilla bean pods if you have not already done so.

After the custard has cooled. Cover and put in the refrigerator for several hours or overnight until completely chilled. It is best to work with a well chilled product. If you choose to process the custard after the ice bath, the only problem, which will not really be so much of a problem, is that the end product will not be as smooth. To be frank, sometimes I skip that 'thoroughly chilled' step. Tell no one. However, I must confess that the product turns out better if it is chilled before churning.

Process according to manufacturer's instructions in an ice cream freezer. Remove dasher from the custard. The custard will be soft set at this point, similar to a thick milk shake. Sometimes, it's great to serve it up as is. However, if you prefer a firmer product, put the custard in a covered container and place in freezer for several hours or over night until firm (this is called ripening).