Combine flour, sugar and salt together in a bowl. Add milk, eggs, and vanilla extract; mix well. Stir in water slowly until batter is very thin and no lumps remain. Cover with plastic wrap and refrigerate for at least 30 minutes.
Melt half the butter in a large frying pan over medium heat. Spread a portion of the batter thinly, covering the bottom of the skillet. Cook until edges begin to brown, 3 to 4 minutes. Flip and cook until lightly browned, 2 to 3 minutes more. Spread a portion of chocolate-hazelnut spread on the crepe while still in the pan; roll up and serve on a plate. Repeat with the remaining butter, batter and chocolate-hazelnut spread to make 8 crepes.