Where the action, counter claim, cross claim or plea in intervention is timely brought for relief based on the theory of rescission, whether formerly the action would have been denominated rescission at law or rescission in equity, the service of a pleading on the adverse party shall be deemed sufficient notice of rescission and of an offer to restore the benefits received under the contract. The method of trial to be afforded shall depend on the relief to which the party who brought suit on the theory of rescission is entitled.
Okla. Stat. tit. 15, § 233A