Heat oven to 200°F.
Coarsely grate potatoes and onion with large holes on a hand grater or food processor. If using a food processor, pulse with on-and-off motions to prevent the mixture from becoming mushy.
Place grated potato in colander; squeeze with your hands to remove any excess liquid.
Transfer potato mixture to large bowl. Stir in flour, eggs, garlic salt and pepper.
Heat oil (about 1/2 inch deep) in 12-inch skillet over medium-high heat until drop of potato mixture sizzles in oil. Using 1/3 cup for each latke, spoon the potato mixture into the hot oil.
Gently flatten the latkes in the skillet with a spatula and fry until golden brown and crisp on both sides, about 2 minutes per side.
Drain latkes on paper toweling. Transfer to a plate and keep warm in the oven. Continue to cook the latkes in batches, adding oil as needed. Serve warm with sour cream and Chunky Applesauce.
Wash and core apples; coarsely chop. In large saucepan, cover apples with water; add sugar and cinnamon. Cook over medium heat for 10 to 20 minutes or until soft. Mash with potato masher or fork for coarse texture.