In a medium bowl, combine the cornmeal, flour, baking powder, baking soda, sugar, and salt. In a small bowl, beat together the buttermilk, egg, and 2 teaspoons of the melted butter. Whisk into the cornmeal mixture until very smooth. (For thinner blini, add a tablespoon or two more buttermilk to the batter.)
Heat a large heavy griddle or skillet over moderate heat until a drop of water bounces across the surface. Brush the surface lightly with melted butter.
Drop the batter, 2 tablespoons at a time, onto the surface, leaving enough room for the pancakes to spread (the blini will be about 2 to 3 inches in diameter).
Adjust the heat if necessary to keep butter from burning. Cook the blini until the surface is bubbled and set and the edges of the undersides are brown. Flip the blini and cook until the second side is browned.
Serve the blini as they come off the griddle, or keep them warm, layered in (and covered with) clean tea towels in a low (200°F) oven; just before serving, brush them with a little melted butter. Repeat until all the batter is used, brushing the pan with butter before each batch.
Cornmeal and Wild Rice Cakes.
Use the bacon fat rather than butter. Stir 2/3 cup cooked wild rice, blotted dry on paper towels, into the batter.
Blueberry Cornmeal Cakes.
Add ½ cup blueberries to the batter.