Have on hand fresh spring roll wrappers. Keep covered so they won't dry out.
Cook vermicelli by pouring boiling water over it and letting it stand for 5 minutes. Drain.
Combine vermicelli, onion, garlic, mushrooms, black pepper, salt, veal, spring onions and cabbage in a bowl and mix thoroughly.
Mix flour and water together to make a smooth paste to use in sealing the rolls.
Place 1 good packed tablespoon of mixture on each wrapper. Moisten edges with flour and water mixture, fold in sides and roll and seal, turning the sealed edges to the underside.
Continue to prepare and place on baking sheets. Allow space between rolls. Brush with oil and bake in a moderate oven until brown and crisp; about 40 minutes.
Spring Rolls may be frozen and reheated in low oven for 20 minutes.