First make the pickles. Cut the cauliflower stem, also reserve any intact and crispy cauliflower inner leaves. Peel and dice stem into 1x1cm cubes. Peel and slice carrot, slice celery stalk. Thinly slice garlic cloves and add all vegetables to a big bowl and sprinkle with the salt. Mix and let stand for 15 minutes.
Meanwhile combine water and sugar in a small saucepan, bring to the boil and mix until sugar has dissolved. Take the pan off the heat, add the vinegar and mustard seeds to the liquid. Prep and sterilize a few glass jars.
Quickly rinse the vegetables in cold water and pack in jars. Pour over slightly cooled pickling liquid and seal, let the pickles marinate for at least half a day, transfer them into the refrigerator when cooled down to room temperature. The pickles will keep in the fridge for up to two weeks.
Cut a big piece of good sourdough bread and butter it. Grate a generous pile of Appenzeller® cheese onto the bread an broil in a hot oven until the cheese melts and bubbles. When still hot, spoon over lots of house pickles and serve as is, or cut into wedges for serving.