Mix the flour, salt and yeast in a bowl. Whisk together the milk, butter, egg yolk and maple syrup, add to the flour, mix to form a smooth batter. Cover the batter and leave to stand at room temperature for approx. 1 hr.
Heat the clarified butter in a non-stick frying pan. Reduce the heat, cook the blinis in batches, using approx. 1½ tbsp of batter per blini (approx. 5 cm in diameter), cook over a medium heat for approx. 3 mins. on each side. Remove the blinis from the pan, drizzle with maple syrup, serve with crème fraîche and caviar.