Salad Olivier - The modern version contains peas, potatoes, carrot, eggs, etc.   It would be cool to cut everything into same-size spheres... 
Not the answer you expect.  Cream freezes at 31.5 F.  Put it in a covered bowl and float it in ice water.   Better yet a cooler with ice water you can close.   Not only do you have an optimal temperature but liquid versus air heat transfer is like 100:1.  Liquid density is like 1000:1.  You can drop a beer can in ice water and have a cool refreshment in 10 minutes.  If you insists on fridge / freezer I would do 1 hr rotation fridge (first) then freezer until you get what works.  Maybe like 4-6 hours. 