Combine the first seven ingredients in a large bowl. Make a well in the middle of the mixture.
Combine eggs with the buttermilk and mix well; pour this into the dry mixture. Stir until it’s almost combined, pour in the melted butter and then mix just until the butter is worked in. Refrigerate the mixture for 12 hours.
Preheat the waffle iron. Stir in chopped pecans to the batter. Pour about 3/4 cup of batter into the waffle iron and cook until they are golden, crisp, and cooked through. Serve with blackberry curd and maple syrup.