2tablespoonbutter, softened28g, approx - you may want slightly more
1tablespoondemerara sugar(or other coarse sugar)
Instructions
Preheat the oven to 350F/180C. Lightly butter a baking dish around 10in x 7in (25cm x 18cm).
Cut the panettone into slices, around ½in/1.2cm thick. If slices are large, vut then into slightly smaller pieces to be able to fit in the dish more easily.
Place the milk, cream and vanilla paste in a saucepan and warm over a medium low heat, stirring now and then, so that it becomes warm but does not boil (it should become close but you don't want it boiling).
Place the sugar and eggs in a bowl and whisk them together so that the sugar dissolves and the mixture becomes slightly paler and glossy. Mix lemon zest into the mixture then set aside.
Butter the slices of panettone (I generally just do one side but you can do both if you like) then layer in the baking dish, with the slices slightly overlapping each other so that they fill the dish.
Once the milk mixture is warm, add a little to the egg mixture, while whisking quickly, to temper the eggs. Once whisked in, add a little more of the milk mixture, whisk in, then keep adding and whisking until it is all incorporated.
Pour the egg-milk mixture over the panettone pieces, being sure to pour over each piece so that each absorbs some of the liquid.
Sprinkle the demerara sugar evenly over the top then bake until the top is gently golden and slightly crisp, around 30 - 35 minutes. Best enjoyed warm.
Video
Notes
If it suits your schedule more, you can make ahead, cover and refrigerate after pouring the egg-milk custard mixture over the panettone. It can soak a few hours, then add the demerara sugar shortly before baking.