Preheat oven to 350 degrees F (175 degrees C). Line a rimmed baking sheet with a silicone pad. Place an 8x11-inch baking dish on the pad.
Place corn in a blender or food processor. Add maple syrup, eggs, milk, kosher salt, cayenne pepper, flour, and baking powder. Mix briefly with a spatula to push down the dry ingredients.
Pulse mixture until it begins to come together. Then increase setting to high and blend until completely smooth, 2 or 3 minutes. Transfer mixture to a mixing bowl. Add heavy cream and 2/3 of the melted butter. Whisk to thoroughly blend.
Grease baking dish with the rest of the butter. Pour batter into baking dish. Bake in preheated oven on the baking sheet until pudding is browned and set, between 60 and 75 minutes depending on the size and shape of your baking dish.