Squeezing the potato mixture with your hands removes excess liquid before dropping it into the hot oil. This will ensure crisp latkes and keep the oil from splattering.
Scrub baking potatoes; do not peel. Shred potatoes and onion in a food processor; drain, pressing between paper towels.
Place potatoes and onion in a large bowl; stir in eggs and next 3 ingredients until combined.
Pour oil to a depth of 1/2 inch in a large heavy skillet over medium-high heat; heat oil to 350°. Squeeze about 1/4 cup potato mixture firmly in hand to remove excess liquid; carefully drop into hot oil. Fry, in batches, 3 to 4 minutes on each side or until golden. Drain on paper towels. Place drained latkes on a wire rack on an aluminum foil-lined baking sheet. Keep warm in a 200° oven up to 30 minutes. Serve with applesauce.