In a blender, add one bag of frozen corn, the 4 eggs, sugar, milk, heavy cream, melted butter, and salt.
Blend on high until smooth and pureed, about 1 minute. Transfer to a large bowl.
In a small bowl, whisk together the flour and baking powder, then whisk that into the blended mixture until combined.
Add the second bag of frozen corn, the pepper, and the chives; stir to combine. (Make-ahead: the batter can be covered and refrigerated for 1 day at this stage.)
Preheat the oven to 350F and grease a 9×12 casserole dish. Pour in the batter.
Bake for 40-45 minutes, until golden brown and a toothpick comes out clean. (If using a 9×13 dish, lessen the baking time by 5-10 minutes.) Serve immediately.
