Cook the macaroni in boiling salted water for about 10 minutes. Pour into a sieve, quench and drain. In the meantime dice bacon finely. Peel and finely dice the onion. Clean, wash and halve the cherry tomatoes.
Clean, wash and cut the Chinese cabbage into strips. Drain the bacon in a pan, take it out and put it aside. Add onion to the frying fat and fry until transparent. Add the Chinese cabbage, fry briefly while turning.
Add tomatoes and bacon. Season with salt and pepper. Mix sour cream and eggs. Season vigorously with salt, pepper and nutmeg. Grease an ovenproof dish (e.g. tart dish 28 cm Ø). Line the tin from outside to inside alternately with macaroni and cabbage.
Pour egg custard over it. Sprinkle with cheese and bake in the preheated oven (electric: 200 °C/ gas: level 3) for 45-50 minutes. Cover if necessary 15 minutes before the end of the baking time. In the meantime, wash the chives, dab dry and cut into small rolls.
Remove the casserole from the oven and sprinkle with chives. Serve garnished with chives and cherry tomato.