Chipotle workers are trained to give you smaller portions of these 7 ingredients

Chipotle teaches employees to moderate servings of seven specific ingredients.

The ingredients, called the "critical seven," include steak, carnitas (pork), barbacoa (shredded beef), chicken, cheese, guacamole and sour cream, the Wall Street Journal reports.

If a customer asks for an extra serving of some of those ingredients, including the meat and guacamole, employees are instructed to charge them more money.

That's because the "critical seven" are the company's most expensive ingredients.

According to an illustrated guide given to employees, the appropriate servings for every order are a 4-ounce scoop of meat and rice, 2 ounces of salsa, and 1 ounce of cheese or lettuce, the Journal reports.

Beef prices are continuing to squeeze Chipotle's profit margins.

Steak and barbacoa burritos cost the company $1 more to make than alternatives like chicken or vegetarian, executives told investors during an earnings conference call.

Global droughts have led to a shortage of beef. Chipotle has started serving conventionally-raised steak in some markets to meet demand.

Consumers do eat some of that $1 cost. A steak or barbacoa burrito costs about 69 cents more in New York City. In cheaper markets like Ohio and Texas, customers pay about 40 cents more.

Chipotle executives said it could raise prices of beef items this summer if the shortage continues.

The burrito chain says that last time they raised prices on steak and barbacoa, they didn't see customers trade down to cheaper options.

The company prides itself on serving "food with integrity." This means antibiotic-free, naturally raised meats and local produce.

Chipotle's high standards have led to a shortage of carnitas.

Hundreds of restaurants have stopped serving pork after the company found that suppliers weren't meeting its standards.

Ashley Lutz contributed to this story.