Combine the milk, heavy cream, salt, whole vanilla bean and 3/4 cup of the sugar into a saucepan; over medium heat. Bring just to a gentle boil stirring frequently. Continue stirring while you add the rice; turn heat to very low.

Cover the saucepan and simmer for 20 to 30 minutes, just until rice is cooked (it should be soft but not mushy).

Remove the saucepan from burner and let cool at room temperature for a few minutes.

Remove the vanilla bean, then start stirring the mixture gently while you add the remaining 1/4 cup of sugar, stirring until the sugar dissolves.

Ladle about a cup of rice mixture into a separate bowl and stir until room temperature, then, while stirring, add the egg yolk, combining it well, then add back into the saucepan with the rest of the rice mixture and stir to combine well; let entire mixture cool to room temperature.

Add most of the whipped cream topping to the saucepan (reserve about 1/8 of a cup) and stir to combine, then pour mixture into a broiler-proof shallow dish and spread the remaining whipped cream topping evenly over the top of the mixture.

Heat the broiler.

Put dish under the broiler and cook just long enough for the top to get golden brown.

Remove and refrigerate (uncovered) until chilled.