Set up a sous vide water bath.

Pour one cup of heavy cream and the half and half into a saucepan and bring it to a simmer. Stir occasionally. Remove the pan from the heat and add the bittersweet and semi-sweet chocolates. Stir to melt. Add the sugar and salt. Add the egg yolks one at a time and mix each one into the chocolate mixture well.

Transfer this mixture to 6 small 4-ounce jars and screw the lid on so that it is just fingertip tight. Lower the mason jars into the un-heated sous vide water bath. Set the temperature of the sous vide circulator to 176ºF and set the timer to 1 hour (or as long as 2 hours). Placing the jars in the water and then turning the circulator on to heat will prevent the jars from cracking with a sudden temperature change.

When the time is up, remove the jars from the water bath and transfer them to the refrigerator until well chilled.

Make the raspberry coulis by combining the raspberries, sugar and a pinch of salt in a blender. Purée completely and add only as much sugar as you need to taste. Pour the raspberry coulis through a fine-mesh strainer and set aside. Set aside.

Let the puddings sit out on the counter for 30 to 60 minutes before serving. Whip the remaining ½ cup of heavy cream until it forms soft peaks. Pour a layer of raspeberry coulis on top of the chocolate and then dollop or pipe a little whipped cream on top. Rest a chocolate heart in the cream and serve.