How do I make crispy potatoes in the oven - how do you get them all crunchy and yummy?

[Shitemum]

Do I have to boil them first?
Cover with tinfoil?

Have a proper oven for the first time in 20 years so I don't have much of a clue...
Thanks!

Par-steam them if you are worried about nutritional value and/or use the veg water in the gravy. But it is Christmas ...

Message withdrawn

...or instead of the flour/cornflour you can use semolina after you've bashed them, that makes them really crunchy.

Message withdrawn