- Position oven racks in top and bottom thirds of oven. Preheat oven to 350F. Slice croissants in half horizontally and toast in the oven on 2 baking sheets, switching sheets halfway through, until slightly crisp, about 3 min. Meanwhile, stir brown sugar with walnuts, butter and cinnamon in a medium bowl until well mixed. Mixture will be wet.
- Whisk eggs in a large bowl. Whisk in granulated sugar, rum and vanilla extracts, nutmeg and salt until combined. Then whisk in milk. Standing croissants up slightly, arrange bottom halves in 2 rows, alternately overlapping them slightly in a 9 x 13-in. baking dish. Scatter half of brownsugar mixture overtop.
- Ladle half of custard mixture over croissants. Lay remaining croissants, top-side up, in 2 rows, alternately overlapping them slightly. Pan will be extremely full. Scatter remaining brown-sugar mixture overtop. Pour in remaining custard mixture. Using your hands, press on tops to make sure croissants are covered in custard. Let sit for another 5 min to soak up liquid.
- Place dish in a larger baking pan in centre of oven. Pour hot tap water into larger pan, halfway up the sides of baking dish. Cover with foil and bake for 25 min, then remove foil and continue to bake until a knife inserted in centre and sides of pudding comes out clean, 35 to 40 more min. Lift baking dish out of water bath and cool on rack. Dust with icing sugar.
Protein 19 g
Carbohydrates 98 g
Fat 46 g
Fibre 4 g
Sodium 970 mg
Day-old croissants are best for this pudding because they will soak up all the liquid. To make ahead, prepare custard and refrigerate. Toast croissant halves. Assemble and let stand while preheating oven.