Speed is helping fuel fast casual restaurants: Analyst

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Chipotle restaurant workers fill orders for customers on April 27, 2015 in Miami.

Restaurants that take advantage of add-on menus, or low-priced items that diners can order as part of a larger meal, have been most successful, the analyst said.

“You still have a low base price, but people come in and buy other things as well,” Hottovy said.

Still, Morningstar placed a hold rating on both Chipotle and Darden and said the companies could benefit from better workforce training, new products and improved order of operations.

“There’s a lot of excitement that comes from [stocks surging], but you have to balance that with … some tempered margin expectations,” Hottovy said.