What is the test for an appeal against a finding that the evidence at trial was insufficient to support the finding?

Citing inferences from evidence favorable only to their conclusions, the appellants allege in conclusory fashion that the evidence at trial was insufficient to support the trial court's judgment. On appeal for sufficiency of the evidence, however, "we consider the evidence in the light most favorable to the prevailing party, accept as true all the evidence and reasonable inferences tending to establish the correctness of the jury's finding, and resolve every conflict in favor of the judgment." (Grassilli v. Barr (2006) 142 Cal.App.4th 1260, 1277.)