Place diced apple, sugar and raisins in a small pot, add 1/4 cup water, sprinkle with cinnamon, pinch of nutmeg, cover, and cook over low heat until soft, 16 to 18 minutes.
Set aside to cool.
Divide the yogurt in 2 medium bowls. Top with apples and chopped nuts. Serve immediately.
Notes
For a Make Ahead If you want to prepare the apples in advance, refrigerate them in a separate bowl then add along with the nuts just before serving.