The persist creature does not have a -1/-1 counter on it.
You control your commander.
Steps
Activate Bloodflow Connoisseur by sacrificing the persist creature.
When the persist creature dies, it triggers, returning it from your graveyard to the battlefield without a -1/-1 counter on it due to your commander's ability granted to it by Master Chef.
Resolve the Bloodflow Connoisseur ability, putting a +1/+1 counter on it.