Ok, so more than just a potato cake.
Do you have a food processor? Some people like to use the shredder blade and some use a "kugel blade" which gives more of a mushy result.
Here's a small recipe if you want to try it:
Peel and shred 5 potatoes and one small onion
You may transfer to a bowl now if it's easier to mix (depends on the food processor)
Add 4 eggs and a generous splash of oil and mix
Add salt and pepper (about a teaspoon of salt and a pinch of pepper)
Mix
Pour into a greased pan and cook on 425 until it has a nice golden/brown crust