One way is to use Service broker. Set the procedure that you want to run async as the activation procedure for a service broker queue and send a message when you want to execute it.
Other option is to create a SQL job with a call to that proc as the only step, then start the job to exec it.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability
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