Grate potatoes coarsely; salt lightly, and allow to drain in colander for about 30 minutes.
Fry onions and shallot in ¼ c. chicken fat or olive oil for about 5 minutes. Move to a cold burner, add potatoes and pepper, and mix well. Allow mixture to cool for a few minutes; add beaten eggs.
Preheat 10-inch cast iron skillet and warm the second ¼ cup of fat or olive oil in it. Turn potato mixture into skillet; smooth top with spatula. Bake for 50 minutes, uncovered. Before serving, brush top with a little chicken fat or oil; set about 6 inches below broiler and broil until top becomes crispy.
Serve with sour cream.
This recipe is adapted from Joan Nathan’s wonderful recipe book The Jewish Holiday Kitchen. You could call this a latke by another name: it’s definitely potato-y, onion-y, totally delicious, and a lot less messy to make.