A great snack or side for your Passover Seder. This recipe is gluten free (GF), nut free, and vegetarian. You can easily double or triple this recipe or substitute the sweet potatoes for standard russet potatoes. If you don't need your knishes to be gluten free or kosher for Passover you can substitute all-purpose flour for the potato starch.
Preheat your oven to 375°F. Poke the sweet potatoes all over with a fork. Bake until soft. Remove from the oven and let cool.
Once cooled, remove the skin from the sweet potatoes and mash in a large mixing bowl. Combine with half the 1/2 the potato starch (1/2 a cup), one of the beaten eggs, and the salt and pepper. Use a fork to combine thoroughly.
Take about a a golf ball sized amount of the sweet potato mixture and shape it in to a disc. Dust the disc in remaining potato starch, then dip in the other beaten egg, and finally coat in the potato flakes. Repeat until you use all of the sweet potato mixture.
Put about a 1/2" of oil in a frying fan and put on the stove over medium heat. Fry on each side until golden brown.