Grate the potatoes using the grating disc of your food processor or by using a box grater.
Take half of the grated potatoes and add them back to a food processor and pulse a few times until they start to resemble mashed potatoes. You want half to be grated and half to be a mashed consistency. This will ensure creamy, but crunchy latkes.
Drain all water from the potatoes by using a nut milk bag or cheese cloth. This step is very important. If you don't remove all of the water, the latkes will take a long time to crisp up and they will possibly burn before that happens. Once all the water is removed, add the potatoes to a large bowl.
Throw the leeks and shallot into the food processor and pulse until it starts to look like a paste. Using the nut milk bag squeeze out the moisture from the leeks and shallots. Add leek mixture to potatoes
In a small bowl, beat the egg with the salt and pepper. Pour egg mixture over potatoes and leeks, and mix well.
Add flour, baking powder, and cheddar cheese to the mixture and mix well.
Heat enough oil(avocado oil or oil of your choice) in a large skillet to cover the bottom of the pan. Use medium heat. Once oil is hot, drop spoonfuls of the potato mixture into the oil. I use a heaping tablespoon and then I use the back of the spoon to flatten the latke once it is in the oil. Do not move the latke for about 3 minutes. Once one side is golden brown, flip it over and brown the other side.
As the latkes are cooking, transfer them to a paper towel lined baking sheet to absorb excess oil.
