Wash the kohlrabi and trim off the leaves and root ends generously. Slice thinly on a slicer or mandoline without peeling. Steam or blanch the slices in salted water until just tender.
Heat a little olive oil in a pan and sauté the zucchini and mushrooms briefly, one after the other. Season well with salt and pepper, then let cool.
Combine the cooled vegetables with the mozzarella and quark (or ricotta). For a firmer texture, mix in about ½ tablespoon of breadcrumbs. Spoon or pipe the mixture onto the kohlrabi slices, roll them up, and chill until ready to serve. Before plating, gently reheat the rolls – ideally in the microwave or over gentle steam – just until warm.
For the tomato ragout, heat the diced tomatoes with olive oil, herbs, and spices in a saucepan. Season to taste and spoon the warm ragout onto serving plates. Arrange the kohlrabi rolls on top, garnish with arugula and shaved Parmesan, and finish with a drizzle of olive oil. Serve immediately.
Recipe by: Andreas Köhne