Whip the cream with a mixer until stiff peaks form.
Meanwhile, in the microwave the 8 oz of the white chocolate for 10 seconds at a time until melted.
Chop the other 8 oz of white chocolate into chunks
Then using a rubber spatula, gently fold in the can of sweetened condensed milk and melted white chocolate and white chocolate chunks.
In a small bowl, stir together the raspberry jam and warm water until smooth
Layer one third of the whipped cream mixture in the bottom of a 2 quart bowl or pan. Drizzle one third of the raspberry jam and gently swirl with a knife.
Repeat the layers two more time.
Cover tightly with a plastic wrap and freeze for at least 6 hours.