(FORTUNE Small Business) – Coke vs. Pepsi. Burger King vs. McDonald's. Color-A-Cookie vs. FooDoodler? The latest brand war isn't among megacorporations but between two small firms that make color-and-eat cookies. And the battle is getting messier than a Pollock-splattered pastry.

The rift began in 2000 when Color-A-Cookie, based in Plainview, N.Y., began packaging printed cookies with food-coloring pens. That irked specialty-ink company Private Label Products in Fair Lawn, N.J., which has sold its own edible-ink markers, FooDoodlers, since 1999. "Suddenly we have competition trying to go around our patent," says founder James Michael.

Why is the product drawing such fire? Because the cookie packs--already available at Toys "R" Us and F.A.O. Schwarz--promise to pull in some serious dough. "They're a great idea," says industry expert Andrew S. Whitman, a former brand manager for Kraft.

Now, Michael says, he's started negotiations to ensure that "everyone is doing the right thing." David Wild, Color-A-Cookie's president, replies that food-coloring pens were around before FooDoodler's patent, and "the taste of our cookie is far superior." Can it be long before these artistic differences find their way into court? -- MAGGIE OVERFELT