| Hawkins |
I think the fastest way would be to use the salamander as a template, switch the creature type to undead, swap the fire-abilites for cold-abilities (and vice-versa), increase the speed from 20 ft. to 30 ft., swap the constrict ability for a constant aura of cold effect, and increase its hit dice by two (bringing the total to 106 [10d8 + 40]). This should produce an approximately CR 7 monster. Then you can add the advanced simple template any number of times to increase the CR further.
--Tim