3 tablespoons brown sugar (or 2 tablespoons maple syrup)
¼ teaspoon sea salt
pinch freshly ground cardamom (optional)
3 tablespoons butter
For the cream:
¼ cup heavy cream
2 tablespoons sour cream
1 cup fruit (such as berries, figs, peaches…)
Preheat oven to 325F.
Combine the oats, cornmeal, sugar, cardamom (if using) and salt in a small bowl. Smush in butter with your fingertips. Scatter clumps onto a sheet tray, and bake until lightly golden brown, 20-25 minutes, stirring halfway. (It will continue to crisp up as it cools.)
While waiting for the crumble to cool: whisk heavy cream and sour cream to medium-stiff peaks. Gently fold fruit into cream. Divide between bowls, and sprinkle with crumble.