Jackman used what he called the “16-8 diet,” meaning he fasted for sixteen hours a day, skipping breakfast and eating from ten in the morning until six p.m. at night. During the feeding window he ate very high calories (5,000), most of which came from lean meats and vegetables (chicken breasts and spinach). Looks like he had to have high calories in order to regain some mass he lost in a previous movie role (Les Miserables). I’ve also notice Jackman is more of an ectomorph (skinny, leaner body type), so maybe that’s another reason he had to go with such high calories.
If you are looking for a similar plan I’d highly recommend you check out Jason Ferruggia’s Renegade Diet. I think you’ll find it to be a worthwhile resource on intermittent fasting for losing fat and/or gaining muscle.