McDonalds’ signature french fries are getting an added boost. The company is now experimenting with seasoned fries.

McDonald's is experimenting with seasoned fries.

The new fries are being offered to customers in Northern California and St. Louis. Three seasonings have been introduced to McDonald’s fans- Garlic Parmesan, Zesty Ranch and Spicy Buffalo.

The fries don’t come preseasoned. Instead, customers are given an order of plain fries along with a packet of seasoning and a specialized mixing bag.

The DIY seasoned fries concept first appeared in Hong Kong markets about 10 years ago. Since then, it spread to locations in China, India and Australia.

The decision to launch in the US could be related to flat April sales. Thus far, sales this year have been disappointing. U.S. same-store sales have actually dropped 1.3 percent.

The chain hopes the seasoned fries will give them a needed boost. A McDonald’s spokesperson, Lisa McComb made it clear the new seasoned fries are only an experiment.

She remarked "As with all tests, we aren't in a position to draw conclusions or make assumptions about the test, since it is just beginning."