Back in 1983 the regional Mexican chain was returning -16% annually. They changed the way they made their food to make it quicker and much cheaper. Instead of preparing everything fresh on-site, the various elements were prepared in centralized commissaries and then delivered to the individual locations to order. When a customer ordered an item, the ingredients would just be combined on-site, giving faster delivery and a much cheaper, centralized ingredient regulation.
As a result they were able grow to an international chain worth $1.98 billion some thirty years later.