The latest funding round for the meatless burger maker brings the startup’s total raised to more than $750 million. : May 13 (Reuters) - Impossible Foods, which makes a meatless plant-based burger and is backed by celebrities like Serena Williams and Katy Perry, said on Monday it has raised $300 million in the latest round of funding ahead of a possible initial public offering. The fundraising underscores the growing appeal in plant-based food that tries to taste like meat with fewer environmental or health risks.