Grate the potatoes and onion using the large holes of a box grater. Transfer to a clean kitchen towel and squeeze out as much liquid as possible. The drier the mixture, the crispier the latkes.
In a large bowl, whisk the eggs. Add the flour, salt, black pepper, baking powder, and oil. Fold in the squeezed potato-onion mixture until fully combined.
Heat a cast iron skillet or heavy-bottomed pan over medium heat and lightly grease with oil. Scoop about ¼ cup of the mixture into the pan and gently flatten.
Cook for 3 to 4 minutes per side, until deeply golden and crisp. Transfer cooked latkes to a wire rack or keep warm in a 250°F oven while finishing the remaining batter.
Serve latkes warm and top with desired toppings from the sampler options.
