And he is scheduled for trial today in Washington County District Court on several unrelated dumpster fires, court records said.
After the jury delivered its verdict Tuesday, Judge Kennedy Boone ordered Cotton held without bond pending completion of a pre-sentence investigation.
Key testimony Monday came from Richard G. Loudin, 19, and his girlfriend, April Green, 17, both friends of his who live on Manor Drive - directly across from the burned restaurant.
Loudin said he was with Cotton at the rear of the House of Kobe and watched him around the loading dock where the fire broke out a short time later.
April Green said Cotton woke her up early that morning and told her to "come see what I did'' and proceeded to take her down to watch the restaurant burn.
While Cotton put on no defense, his attorney, Steven Kessell, stressed to the jury that neither Green nor Loudin came forward with this information until March.
Cotton's name surfaced in interviews with Loudin, Green and others, testimony from Hagerstown Fire Marshal Tom Brown revealed.
Brown said they told him that Cotton set the fire as a prank because he "had nothing better to do.''
The fire destroyed the restaurant and left at least six employees temporarily without jobs.
The fire was started in the rear of the restaurant at 757 Dual Highway, authorities said.
Massy Hirai, owner of the restaurant, testified the loss was about $200,000. Construction on a new restaurant at the old Dual Highway site is expected to be finished by November.
The restaurant moved to temporary quarters in the Dagmar Hotel building on the corner of Summit Avenue and Antietam Street downtown, Hirai said.