3 cups white cornmeal
1 cup all-purpose flour
2 tablespoons sugar
2 teaspoons baking powder
1 1/2 teaspoons salt
1 teaspoon baking soda
7 large eggs, divided
3 cups buttermilk
3 cups soft breadcrumbs
2 medium onions, diced (2 cups)
1 large bunch celery, diced (3 cups)
1/2 cup finely chopped fresh sage (or 1 T. dried)
6 (10 1/2-ounce) cans condensed chicken broth, undiluted
1 tablespoon pepper
Place 1/2 cup butter in a 13- x 9-inch pan; heat in oven at 425° for 4 minutes. Combine cornmeal and next 5 ingredients; whisk in 3 eggs and buttermilk. Pour hot butter into batter, stirring until blended. Pour batter into pan. Bake at 425° for 30 minutes or until golden brown. Cool.
Crumble cornbread into a large bowl; stir in breadcrumbs, and set aside.
Melt remaining 1/2 cup butter in a large skillet over medium heat; add onions and celery, and saute until tender. Stir in sage, and saute 1 more minute.
Stir vegetables, remaining 4 eggs, chicken broth, and pepper into cornbread mixture; pour evenly into 1 lightly greased 13- x 9-inch baking dish and 1 lightly greased 8-inch square baking dish. Cover and chill 8 hours.
Bake, uncovered, at 375° for 35 to 40 minutes or until golden brown.
Notes: I used leftover cornbread to replace the cornbread in the recipe. 1/3 batch fills a 9.5" pie plate.