When I'd frozen the cake-sized "bread", I'd wrapped them tightly in foil and then put that package into a gallon-size plastic freezer bag. Today I made sure to leave it all wrapped up while defrosting to keep in as much moisture as possible. I then removed it from the plastic bag, opened the foil, and did the following:
1) stabbed it many times with a fork, to make holes in the top crust
2) spread 1 to 2 Tablespoon of soft butter over the top
3) sprinkled the top with 1 to 2 Tablespoons of white sugar
4) drizzled 2 to 3 Tablespoons of orange-flavored liqueur (you could use sherry or brandy instead) over that
5) closed up the foil and put it into a low oven (170 to 200 degrees Fahrenheit) for no more than 10 minutes, till butter is melted
It was yummy. I should try this with an unfrozen batch, and will, come next summer.