Which came first, the chicken or the egg? Thanks to  Hampton Creek, we finally have an answer: It was the egg. It just took a lot longer than expected.

The drama-prone food startup, which is working to develop cultivated poultry that can be harvested from a vat without killing any animals, unveiled its long-promised egg-substitute product on Thursday.

At a tasting event for members of the press held at Flore restaurant in San Francisco, CEO Josh Tetrick said the new product, Just Scramble, is an important step in the company's mission of fixing the global food system because eggs the first animal protein people in the developing world eat as they move up the income scale.

A liquid that's only meant to be used for a day or so after thawing, Scramble isn't ready for sale in grocery stores just yet. For now, it's being marketed to the food service industry, where most of the eggs served are supplied to kitchens in pourable form.

As is the case with other Hampton Creek products, like Just Mayo and Just Cookies, the company is playing down the ethical and environmental implications of replacing animal protein with plant ingredients -- in this case, sourced primarily from mung beans -- in favor of emphasizing things like cost, taste and healthiness.

"It's not just a product for conscious consumers," Tetrick said. "It's for diners where a vegan has never walked in the door."

After Tetrick's introduction, Chris Jones and Ben Roche, who together head up Hampton Creek's product development, cooked up scrambled faux-eggs with spinach, mushrooms and goat cheese for guests to try. The dish looked and tasted like good scrambled eggs.

Those who tried the "eggs" without the other ingredients agreed they don't quite pass for the real thing, with a slight aftertaste that's not unpleasant but noticeably un-eggy. Jones, a chef who previously cooked at Chicago's esteemed Moto, agreed: To his refined palate the taste is only 80 percent of the way there, he said. Still, in current tests, Tetrick said, around half of participants in any given test say they prefer Just Scramble to conventional eggs sourced from non-sustainable, non-humane suppliers. "There are some tests where Just Scramble is winning, there are some where the conventional eggs are winning," he said.

The goal, he added, is to improve the flavor to the point where 51 percent of consumers prefer Just Scramble even to the pasture-raised eggs Jones buys for his family from his local farmers market in Marin County. In the meantime, getting Just Scramble onto restaurant-goers' plates is a meaningful step forward for a company that's been big on promises but short on execution.