Pour boiling water over the raisins for 10 minutes, drain in a colander and let dry. Chop the nuts, but not too finely.
Use a paring knife to remove tough fibers from the outside of the rhubarb stem. Cut the stalk across the thinnest slices, salt.
Peel the apples from the peel and core, cut the flesh into strips. Pour in lemon juice.
Mix apples, rhubarb, nuts and raisins, season with yogurt, salt and pepper and serve.