Blackberry Fonio Cobbler With Toasted Benne

Name: Blackberry Fonio Cobbler With Toasted Benne
Ingredients: 1/2 cup uncooked fonio; Softened unsalted butter or neutral oil, for greasing the pan; 4 pint fresh or frozen blackberries (about 8 cups); 1/2 cup plus 2 tablespoons granulated sugar, divided; 1/2 teaspoon Morton kosher salt, divided; 2 teaspoon vanilla extract; 1 tablespoon lemon juice; 1/4 teaspoon ground cinnamon; 1/4 teaspoon freshly grated or ground nutmeg; 3/4 cup all-purpose flour (or a 1:1 gluten-free flour); 1 teaspoon baking powder; 3 tablespoon cold unsalted butter, cut into cubes; 1/3 cup milk of your choice; 1 tablespoon toasted benne or sesame seeds, plus more for serving; Vanilla ice cream or whipped cream, for serving (optional)