You can freeze the potato on the fries
I do it myself (I learned in Belgium, and they invented French fries and the principle of double roasting with a break).
Sliced potatoes on a straw, I likelarger, well washed in cold water from starch, dried and minced for 5 minutes, you have to stir, the potatoes will only slightly change color and become more transparent. Allow to drain off the fat, cool to decompose and into the freezer.
I usually have a packet of such potatoes in case of laziness