Preheat oven to 350 degrees F (175 degrees C). Grease an 11x7 inch baking pan. In a medium bowl, beat sugar, oil, eggs, and vanilla until light and fluffy. Combine the flour, baking powder, salt, and cocoa; stir into the sugar mixture. Blend in the peanut butter. Spread batter evenly into the prepared pan. Bake for 25 to 30 minutes in the preheated oven, until edges of brownies start to pull away from the sides of the pan. Cool before cutting into bars and serving.
Preheat oven to 375 degrees F (190 degrees C). Grease a 9x13-inch baking dish. Mix cornmeal, flour, sugar, salt, and baking soda together in a large bowl. Add sour cream, butter, and eggs; stir until fully incorporated. Pour batter into the prepared baking dish. Bake in the preheated oven until a tooth pick inserted in the center of the cornbread comes out clean, 30 to 35 minutes.