It's not easy to make a healthy crisp: The topping always has lots of butter and sugar. John Currence makes his streusel with a mix of oats, whole wheat flour and brown sugar and a little butter-oil blend to keep it crumbly.
Make the Streusel:
Preheat the oven to 350°. In a bowl, soak the raisins in the hot water for 20 minutes; drain. Stir in the sugars, flour, cinnamon, nutmeg, lemon zest, lemon juice and orange juice. Fold in the nectarines and plums. Scrape the fruit into a 9-by-13-inch glass baking dish. Cover with foil and bake for 15 minutes.
In a bowl, combine the oats, flours, sugar, lemon zest and cinnamon. Work in the butter blend. Press the streusel into clumps and sprinkle over the fruit. Bake the crisp for 30 minutes, until the fruit is tender and the topping is golden. Let cool for 20 minutes, then serve.