All of these attributes are more likely to be provided by multiple sourcing.
However, multiple sourcing can make it difficult to encourage a continued commitment by suppliers to offer consistent and competitive prices. Adjusting or tweaking the menus seasonally offers a potential risk management strategy. Frequent menu changes means Ms. Nok will never be at the mercy of an individual supplier and without bargaining power if, for example, the price of beef suddenly escalates. On the other hand, she will be unable to reduce her orders substantially without incurring a large price hike given that she does not have an exclusive, close relationship with a supplier. Having bulk vegetables, meats, and fish from a single supplier that can be seasoned in unique ways to allow for diversity might be one way to make single sourcing work, and if sympathetic high-quality producers were found with which to establish a relationship, this might satisfy the need for more quality control and diversity.
For dry goods, such as rice or sugar, multiple sourcing seems more advisable, whatever the circumstances. Although single sourcing generally gives the restaurant owner greater flexibility, including the ability to adjust the restaurants use of the product during slow and heavy travel seasons, Ms. Nok could simply negotiate on the open market for the best price possible for nonperishable items, and then buy in bulk given the long shelf life of these items. Various types of rice or sugars and even coffees offered could be kept without substantially curtailing food quality, and even if perishable meats, cheeses, fish, and vegetables were single-sourced, they could still be distinctive and varied if paired with the right spices, coffees, crackers, breads, and other storage-friendly items.
With a high-quality chef, much could be accomplished with the correct spices and sauces.
Even with single-sourcing of dry goods, there is a danger that disruptions in the supply chain could cause a substantial deficit of a staple product — for a coffee kiosk to run out of sugar, for example, would be retail suicide. However, given the ambitions of the Nok restaurant and the diversity of its offerings, multiple sourcing would seem to be the wisest strategy, even essential, for dry goods like spices and coffees. Without a wide range of such products, it is difficult to create the profile of a restaurant that caters to a high-end clientele and purports to be more than a glorified Dunkin Donuts even in its low-end incarnation.
Depending on the relationship offered by the sources of perishable goods, a single-source agreement might be required, to ensure a steady yet flexible and affordable supply of meat and fish. The talent of the chef will also determine if it is feasible that more standardized perishable ingredients can be made to seem interesting with the right single-source nonperishable spices. At present single-source perishable goods strategy from high-quality suppliers and a multiple-source nonperishable items strategy seems wisest..