Aki, it seems that with mexicans fat on the meat is where the flavor is, and in judicious amounts with certain dishes, God help me, I agree.
Some marbling in the meat helps it cook tender and adds flavor regardless of cooking method. Hence the old practice of “larding” tough cuts of meat devoid of fat or connective tissue.
I once trimmed a point brisket clean of fat and smoked it for the requisite temperature and time. It was harder than a rock and a waste of good meat, there was no melting fat to baste it. Good brisket is moist and falls apart with a fork.
There is a difference in the flavor of beans with and without lard or bacon grease, and mexican beans will have some sort of pork fat for flavor.
7th Day Adventists, practicing Jews, vegetarians and certain others would do well for their dietary requirements to avoid beans prepared in latin american restaurants, and probably anywhere else for that matter.
Maybe 20 years ago I had a conversation with a restaurant owner in Ventura about his mexican employees.
He said he had to be after the new employees about trimming fat from meat because the cholesterol would be killing his customers. He was probably also concerned about health conscious customers or those thinking he was cheating them not coming back after finding a huge chunk of fat on their plate.
He had to be on them about cleaning up bits of food that fell on the floor because it would attract cockroaches.
There were other matters of hygiene he usually had to educate them about.
There was a mexican restaurant I patronized between 1987 to 2004 which had unique flavoring and was delicious. It wasn't the typical formula tex-mex dispensary raved about by self appointed google maps "local guides,” ignorant wanna be foodies and obnoxious “influencers” who film and post online everything about every unlikely, frickin' restaurant meal they've ever eaten as “authentic mexican.”
The building, no five star edifice by any means, was in decent repair for its age and place. It was old.
I only recall women working there, they were probably related - extremely common for that type of operation. In their spanish conversation between themselves they could have made a whole aircraft carrier packed full of sailors blush with their potty mouths.
The cockroaches in that place were numerous and they weren't afraid of anyone on earth. They might have even launched a banzai suicide charge on the Orkin man if they had only been smart enough to identify him as the ultimate enemy.
There were probably rodents too.
But the food was super good, and of everyone I knew who regularly ate there, maybe 30 people, I never heard of anyone getting sick.
But it was disconcerting one time I saw a cockroach in the bowl of the restroom urinal (of course I hosed him down) and after reseating myself discovered another traversing the table toward my plate.
I would never again eat in a restaurant with that sort of vermin problem, but it didn't bother me back then for that place.
I've never seen anything like that anywhere else, and I've eaten in some run down, falling apart places, so I'm not suggesting it's typical of mexican eateries to be infested with vermin.
And to be clear, even though I consistently trash those who confuse tex-mex with mexican food, and probably always will, I like good tex-mex prepared by those who put their heart into their creations.
It's no fun to cook only for yourself, and wanting to cook for others is a way of giving a part of yourself to the other, no matter the style.