In a blender, combine the sweet corn, egg, all-purpose flour, salt, and granulated sugar. Blend until mostly smooth, about 30-45 seconds.

Preheat a large skillet over medium heat for about 3 minutes. Drizzle in vegetable oil to coat the bottom.

Pour approximately 60 ml of the batter onto the skillet for each cachapa. Cook for 3-4 minutes until golden brown, then flip and cook for another 2-3 minutes.

Place a few slices of mozzarella cheese in the center of the cooked cachapa and fold in half. Let sit for another minute to melt the cheese.

Transfer cachapas to a plate, top with unsalted butter, and serve immediately.