
Notes
The exact baking time will depend on the depth of your baking dish. Look for a golden topping and bubbling filling rather than relying only on the clock.
Do not boil the custard. Gentle heat keeps it smooth and prevents the egg yolks from scrambling.
The custard will thicken as it cools. Whisk in warm milk one tablespoon at a time if you need to thin it.
Store the crumble and custard separately in the refrigerator. The crumble will keep for up to four days, and the custard will keep for up to three days.