Let's stick with the original spell name and of course we'll convert the creature!
Cocoademon (Conjuration/Summoning)
Level: 4
Range: 1"
Duration: Permanent until dispelled
Area of spell: Special
Components: V,S,M
Casting Time: 3 hours
Saving Throw: None
Explanation/Description: With this spell, the chef creates a 10" tall demon-like creature made of chocolate, which can obey simple instructions from its creator (such as carrying light objects, stealing a small item, sounding an alarm in case of an unexpected visit, etc.). The cocoademon is of low intelligence and, though loyal to its creator, it likes practical jokes and causing mischief (but hates hot temperatures). It has 1 hp per level of the caster and an armor class of 10. The material component is 3 pounds of chocolate.
A 4th-level summon spell can get a mephit, so I imagine the power level similar to one of them. A mephit is 4' tall, though, and this fellow is only 10" tall, so we'll have to downsize it to Diminutive. I figure its consistency is probably closest to ooze, so I'll downsize an Ooze Mephit and add the usual demonic traits:
Demon, Cocoademon
Diminutive Outsider (Chaotic, Evil, Extraplanar, Tanar'ri)
Hit Dice: 3d8+3 (16 hp)
Initiative: +2
Speed: 30 ft. (6 squares), fly 40 ft. (average), swim 30 ft.
Armor Class: 16 (+4 size, +2 Dex), touch 16, flat-footed 14
Base Attack/Grapple: +3/-10
Attack: Slam +6 melee (1)
Full Attack: 2 slams +6 melee (1)
Space/Reach: 1 ft./0 ft.
Special Attacks: -
Special Qualities: Damage reduction 5/cold iron or good, darkvision 60 ft., fast healing 2, immunity to poison, resistance to fire 10, telepathy 100 ft.
Saves: Fort +4, Ref +5, Will +3
Abilities: Str 8, Dex 14, Con 13, Int 6, Wis 11, Cha 15
Skills: 6 at 6 ranks
Feats: 2
Environment: Infinite Layers of the Abyss
Organization: Solitary
Challenge Rating: 3
Treasure: Standard
Alignment: Always chaotic evil
Advancement: 4–6 HD (Diminutive); 7–9 HD (Tiny)
Level Adjustment: +3 (cohort)
Alternatively, we can make it a cocoad
aemon, and give it yugoloth traits:
Cocoadaemon
Diminutive Outsider (Evil, Extraplanar, Yugoloth)
Hit Dice: 3d8+3 (16 hp)
Initiative: +2
Speed: 30 ft. (6 squares), fly 40 ft. (average), swim 30 ft.
Armor Class: 16 (+4 size, +2 Dex), touch 16, flat-footed 14
Base Attack/Grapple: +3/-10
Attack: Slam +6 melee (1)
Full Attack: 2 slams +6 melee (1)
Space/Reach: 1 ft./0 ft.
Special Attacks: -
Special Qualities: Damage reduction 5/good, darkvision 60 ft., immunity to acid and poison, resistance to cold 10, electricity 10, and fire 10, telepathy 100 ft.
Saves: Fort +4, Ref +5, Will +3
Abilities: Str 8, Dex 14, Con 13, Int 6, Wis 11, Cha 15
Skills: 6 at 6 ranks
Feats: 2
Environment: Bleak Eternity of Gehenna
Organization: Solitary
Challenge Rating: 3
Treasure: Standard
Alignment: Always neutral evil
Advancement: 4–6 HD (Diminutive); 7–9 HD (Tiny)
Level Adjustment: +3 (cohort)