In short, the difference between these corn casseroles is technique and temperature.All of them are classified as corn casserole and top holiday side dishes. They use the same ingredients, baked in a casserole dish in the oven. Here's the difference between them. Corn pudding uses minimal flour/starch to thicken the mixture. It's a custard-based recipe. Typically you use less flour (cornbread mix) to bake at 350 degrees to keep the eggs from overcooking (curdling). Corn puddings use between 4-6 large eggs. Corn casserole is a cornbread base dish that uses jiffy or another muffin mix to give the dish that tastes like wet cornbread. Typically corn casserole is baked at 400 degrees. You can bake this one at a high temperature because of the cornbread base. Corn casserole use between 2-3 large eggs. Corn soufflé is an egg white based recipe that relies on the eggs whites being whipped to a stiff peak and folded in the corn mixture. You bake the soufflé at the same temperature as the corn pudding. And use the same amount of eggs as the corn casserole. In short, the difference between these corn casseroles is technique and temperature.