Crepes: Beat eggs slightly, add flour, oat bran and basil. Gradually stir in milk and let mixture stand for a minimum of 15 minutes.
Pour about 3 tbsp batter onto a 6″ (15 cm) hot skillet and quickly rotate pan to spread batter evenly over bottom.
Cook until top is dry and underside golden. Turn crepe and cook for a few seconds on the other side. Continue cooking remaining batter in same fashion.
Filling: Saute mushrooms and onion in butter until just tender. Stir in flour, salt and pepper. Gradually add milk, stirring constantly until thickened. Add cheese and continue to stir until cheese has melted.
Cook asparagus in boiling water until just tender. Drain. Be sure sauce and asparagus are hot, then on each crepe, arrange 3 asparagus spears and about 2 tbsp sauce. Roll up crepe and arrange 3 crepes on each plate. Spoon sauce over crepes and garnish with egg slices. Serve hot.