Shred potatoes and onion
Peel the potatoes into cold water so they don’t oxidize. Fit a food processor with a grater attachment. Grate the potatoes and onions and place into a large bowl.
Squeeze excess moisture
Wrap the mixture in cheesecloth and squeeze all the excess liquid from the potatoes and onions then return them to the mixing bowl.
Combine latke mixture
Add the eggs, matzo meal, baking powder, salt and pepper and use a wooden spoon to combine. The mixture should be wet and thick.
Add the schmaltz and enough oil to fill a large cast iron skillet ¼” of the way up and heat over medium heat until the oil is hot and shiny.
Working in batches to not overcrowd the pan, scoop the latke batter in spoonfuls and use your hands to shape into a small disc.
Add to the hot oil and fry until golden brown on both sides and the edges are crispy, about 3 to 4 minutes total. Remove to a paper towel lined plate to drain.
Assemble and serve
Repeat with the remaining potato mixture. Serve latkes hot topped with crème fraîche, chives and caviar.