In a large bowl, stir together hash browns, egg substitute, flour, green onion, pepper, salt, and baking powder.
Heat 1 tablespoon oil in a 12-inch nonstick skillet over medium heat.
Cook four latkes at a time. For each latke, spread 1/4 cup potato mixture into a 3 1/2-inch circle in the hot skillet. Cook for 4 to 5 minutes, turning once. Repeat with remaining potato mixture, adding more oil to the skillet as needed. Season with salt and pepper if desired.