This is another beautiful recipe from Heidi Swanson of 101 Cookbooks.

Plum and Peach Crisp

Fruit:
1 pound ripe peaches
1 pound ripe plums
1/4 cup natural cane sugar (or brown sugar)
1 tablespoon plus 1 teaspoons arrowroot (or cornstarch)
a scant 1/2 teaspoon orange blossom water (opt)

Crisp:
3/4 cup rolled oats
3/4 cup white whole wheat flour (all-purpose flour)
1/2 cup natural cane sugar (or brown sugar)
1/2 teaspoon cinnamon
big pinch of salt
1/3 cup butter, melted
1/3 cup yogurt

Preheat the oven to 400 degrees F.

Cut the peaches and plums into bite-sized, 1-inch pieces. Place the chopped fruit in a medium-sized bowl.

In a separate small bowl whisk together the 1/4 cup sugar and the arrowroot. Sprinkle over the fruit, toss gently (but well), add the orange blossom water (optional), toss again, and transfer the fruit to an 8-inch square baking dish (or your favorite equivalent-sized, deep-sided, solid-bottomed tart pan).

To make the topping combine the oats, flour, sugar, and cinnamon together in a medium bowl. Stir in the butter, and then the yogurt and mix until everything comes together in a dough-like texture. Sprinkle the crumble evenly over the plum and peach mixture.

Place the baking dish in the oven, middle rack, and bake for about 20-25 minutes, or until the topping is golden. Sprinkle a bit more sugar on top as it comes out of the ovens, and if you have a lemon on hand, grate a bit of zest on top (optional). Enjoy warm or at room temperature.