Combine milk and cream in a saucepan and bring to a simmer.

In a large bowl, whisk together eggs, egg yolks, sugar, and vanilla extract.

Gradually pour the hot milk mixture into the egg mixture, whisking constantly to temper the eggs.

Add the cubed panettone bread to the custard mixture, gently pressing to soak the bread.

Let the mixture stand for 30 minutes, stirring occasionally.

Preheat oven to 325°F (160°C).

Grease 6 ramekins or custard cups.

Spoon the panettone mixture into the prepared ramekins, pressing gently.

Place the ramekins in a large roasting pan and fill the pan with boiling water to reach halfway up the sides of the ramekins.

Bake in the preheated oven for about 40 minutes, or until a knife inserted into the center comes out clean.

Remove the ramekins from the water bath and let cool to room temperature.

Refrigerate for up to 2 days for best results. (Make-ahead)

Peel and slice the apples.

Melt butter in a large nonstick skillet over medium-high heat.

Cook the apple slices until tender and lightly golden, about 5 minutes.

Run a knife around the edge of each pudding to loosen.

Invert the puddings onto a parchment-lined baking sheet.

Arrange the cooked apple slices over the puddings.

Sprinkle the remaining sugar over the apples and puddings.

Broil 6 inches from the heat until the sugar bubbles and caramelizes, about 2-6 minutes.

Serve immediately.