Peel potatoes and grate coarsely, transferring grated potatoe to a container of cold water. When last batch is added drain the potatoes in a colander and dry on a kitchen towel to remove excess water.
Transfer potato mixture to a medium-sized bowl, stir in onion, roasted garlic, egg and salt.
Heat 1/4 cup oil in a 12-inch nonstick pan over medium-high heat.
Spoon 2 tablespoons potato mixture per latke onto pan, and spread into 3 inch rounds with a fork. Cook until underside is golden-brown and turn over, once, cooking until golden-brown.
Add more oil to pan as needed.
Place cooked latkes on wire rack and keep in oven until ready to serve.