Coarsely blend 2 cups of the corn kernels with 2 tablespoons of buttermilk until it has the consistency of a chunky cream. Reserve the rest.
In a large bowl combine all the ingredients except the butter. Mix well.
Place rack in middle of the oven. With the butter, generously coat a 10 x 15-inch baking pan or 11-inch cast iron skillet and put it in the oven for about 5 minutes or until the butter has melted. Remove from the oven and quickly pour in the batter.
Bake for 30 minutes or until the cornbread begins to pull away from the sides of the pan and a toothpick comes out clean. Cool in the pan. Cut into squares and serve.
To make substitute buttermilk, add 1 tablespoon of lemon juice or 1 teaspoon of cream of Tartar to 1 cup of regular milk.