A “hat trick” in ice hockey is when a player scores three goals in one game. A “Texas hat trick” (somewhat larger than a regular “hat trick”) is when an ice hockey player scores four goals in one game.
 
“Texas” was probably added because of the popular phrase, “Everything’s bigger in Texas.” The Houston Aeros were a professional ice hockey team in the World Hockey Association from 1972 to 1978, but the term does not derive from this WHA team. Canadian Curtis J. Phillips claims to have coined “Texas hat trick” in the late 1970s, but this is also incorrect. “Texas hat trick” is cited in print from at least 1969.
     
   
Wikipedia: Hat-trick
A hat-trick in sports is associated with succeeding at anything three times in three consecutive attempts. In North America it is often rendered as hat trick, with no hyphen. (The Oxford English Dictionary has it unhyphenated and gives a variety of examples published in the 19th and 20th centuries both with and without the hyphen.) 
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Hockey
In both field hockey and ice hockey a hat-trick is when a player scores three goals in a game. Although people may consider a hat trick as three goals scored in a row, this is commonly confused with a natural hat trick (below).
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A natural hat trick is when a player scores three consecutive goals in the same game.
     
Hockey 101
Texas Hat Trick - Four goals scored by a single player in one game.
         
Hockey Glossary
Texas hat trick
A term used to describe when a player scores four goals in a single game.
     
Frozen Hoops
Curtis J. Phillips
Canada’s Basketball Historian
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He is also credited with in the late 1970s’ coining the term “Texas Hat Trick” for four or more goals in a ice hockey game and with standarizing athlete biography sheets that are used in sporting events.
       
18 October 1969, Xenia (OH) Daily Gazette, pg. 7, col. 8:
Hugh Harris of Muskegon scored the “Texas” hat trick last night by scoring four goals. 
 
18 March 1971, Xenia (OH) Daily Gazette, “Gems clinch 3rd place as Benzelock nets four goals,” pg. 7, col. 3:   
Benzelock, who joined the Gems some six weeks ago, posted the “Texas Hat Trick” by hitting an open net with his final tally at 19:47 of the third period.
   
23 February 1974, New York (NY) Times, pg. 21:
He (Gordie Howe—ed.) scored four goals in another game, a “Texas hat trick,” they called it.
     
15 November 1974, Xenia (OH) Daily Gazette, pg. 7, col. 1 photo caption:
If three hockey goals are called a hat trick and four a Texas hat trick, then a five-goal night must be an Alaskan hat trick. 
 
30 October 1980, Deer Park (TX) Progress, pg. 4B, col. 5:
Scott Berry scored the Texas hat trick (4 goals) while Paul Russell netted a pair. 
 
17 December 1985, Philadelphia (PA) Inquirer, pg. D3:
Bellows had his Texas Hat Trick (as they called a four-goal game when Houston was in the World Hockey Association) in a 10-2 win over Detroit on Wednesday. 
 
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From: .(JavaScript must be enabled to view this email address) (David)
Date: Mon, 1 Mar 1993 08:12:30 GMT
Local: Mon, Mar 1 1993 3:12 am
Subject: texas hat trick
   
I was watching CNN sports tonight (sunday), and in reporting the Winnipeg Minnesota game, they said that Selanne had a ‘texas hat trick’. What the heck does that mean? I’ve never heard that before.
   
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From: .(JavaScript must be enabled to view this email address) (Ali Lemer)
Date: Mon, 1 Mar 1993 18:54:29 GMT
Local: Mon, Mar 1 1993 1:54 pm
Subject: Re: texas hat trick
 
In article <1993Mar1.112429.20…@nntp.hut.fi> .(JavaScript must be enabled to view this email address) (Markku Lehtinen) writes:
>> [What’s a “Texas Hat Trick”?]
>Four goals in one game?
 
Wouldn’t that be a Baker’s Hat Trick?
 
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From: Chris

Date: 1996/10/02
Subject: Re: HOCKEY SLANG summary  
 
Texas Hat Trick: 4 goals in a game (you know, everthing is bigger in Texas)