The Hornets flew out to Spain on Monday having struggled to train at their London Colney base due to the cold snap which has swept through Britain for the past week.
And they capped off their stay on the continent with a 3-0 friendly victory over Shanghai East Asia, with Troy Deeney, Jonathan Hogg and Geoffrey Mujangi Bia on the scoresheet.
Speaking ahead of their return to Hertfordshire on Thursday, Zola told the club's official website: "Training has been going very well.
"The weather wasn't ideal back at home so we've been able to go about our usual training session in the warmer weather.
"Training itself has not been too different, the biggest change has been the environment and overall there have been many positives.
"The facilities have been excellent and it has been useful for the squad to spend some more time together."