“Finger-lickin’ good” is the popular slogan of KFC restaurants (formerly known as Kentucky Fried Chicken). “Finger licking” food is so good that one would rather lick fingers than wash them.
 
Kentucky Fried Chicken trademarked the slogan, with a first date of use from April 30, 1952. An Oregon restaurant advertised its chicken dinner “It’s finger-lickin’ good!” in July 1953; Baker’s Coconut was advertised as “finger-lickin’ good” in November 1953. “Finger-lickin’ good” has sometimes been used to generically describe any tasty food, but the trademark phrase retains worldwide identification with KFC.
 
   
Wiktionary: finger-lickin’ good
Alternative forms
finger licking good
Etymology
Colloquial phrase made popular in early advertising of Kentucky Fried Chicken, a US fast-food operation.
Adjective
finger-lickin’ good (comparative more finger-lickin’ good, superlative most finger-lickin’ good)
1.(colloquial, US) Extremely good, usually in reference to food, but can refer to anything lickable or anything that can be said to be delicious.
     
Google Books
No More Than Human, a novel
By Maura Laverty
New York, NY: Longmans, Green and Co.
1944
Pg. 35:
Every recipe in Juanita’s repertoire was, as the Spaniards themselves say, “finger-licking” — para chuparse los dedos.
 
12 July 1953, The Oregonian (Portland, OR), pg. 2, col. 7 ad:
SLIM SEZ:
IT’S FINGER-LICKIN’ GOOD!
$1
Barbecued
CHICKEN DINNER
(...)
OAK PIT BARBECUE
 
Google Books
16 November 1953, Life magazine, pg. 109 ad:
Fluffy, new no-cook frosting—
finger-lickin’ good with new Baker’s Coconut
 
3 November 1955, Lowell (MA) Sun,
WE’RE REALLY CROWING ABOUT OUR FINGER LICKIN’ CHICKEN!
(Stop & Shop Super Markets—ed.)
 
12 November 1955, Wisconsin Parids (WI) Daily Tribune, pg. 2, col. 1 ad:
THE GATE
Weekend Specials
RIBS
Bar-B-Qued—Prepared to a finger licking delight
$1.50
 
29 September 1957, Idaho Sunday Journal (Pocatello, ID), pg. 33, col. 5 ad:
Broasted Chicken is finger lickin’ good
THE POLAR BEAR
 
22 August 1958, Winnipeg (Manitoba) Free Press, pg. 10, col. 6 ad:
It’s Delectable—It’s Original—It’s Finger-Licking Good
That’s The Way To Describe
KENTUCKY FRIED CHICKEN
 
22 May 1959, The Plain Dealer (Cleveland, OH), pg. 4, col. 2 ad:
SHEFFIELD HOUSE RESTAURANT—At the O’Neil Sheffield Shopping Center, Rt. 254 (Detroit Road between Elyrie and Lorain). You haven’t really enjoyed chicken until you have tried our specially prepared “Col. Sanders’ Kentucky Fried Chicken”, made from a famous, old Southern recipe. It is truly “Finger Licking Good”.
 
OCLC WorldCat record
Life As I Have Known It Has Been Finger Lickin’ Good
Author: Harland Sanders
Publisher: Carol Stream, Ill. : Creation House, 1974.
Edition/Format:  Book : English
 
(Trademark)
Word Mark IT’S FINGER LICKIN’ GOOD
Goods and Services IC 029. US 046. G & S: Prepared chicken for consumption on or off the premises. FIRST USE: 19520430. FIRST USE IN COMMERCE: 19520430
IC 030. US 046. G & S: gravy. FIRST USE: 19520430. FIRST USE IN COMMERCE: 19520430
Standard Characters Claimed
Mark Drawing Code (4) STANDARD CHARACTER MARK
Serial Number 78506637
Filing Date October 27, 2004
Current Basis 1A
Original Filing Basis 1A
Published for Opposition October 4, 2005
Registration Number 3035298
Registration Date December 27, 2005
Owner (REGISTRANT) KFC Corporation CORPORATION DELAWARE Legal / Trademarks 1441 Gardiner Lane Louisville KENTUCKY 40213
Attorney of Record Eliane Setton
Prior Registrations 0759776;0801095;2216683
Type of Mark TRADEMARK
Register PRINCIPAL
Affidavit Text SECT 8 (6-YR).
Live/Dead Indicator LIVE