Mix the harina de maíz and 2 teaspoons salt. Add the water and whisk to remove any lumps. Stir until combined. Let the mixture rest for 5 minutes covered with a dishtowel.

Preheat oven to 400°. Using your hands, divide the dough into 8 pieces. Roll each piece into a ball and flatten gently to create a disk, about 1/2-inch thick. Heat a thin layer of avocado oil in a large heavy skillet over medium heat. Fry the disks 3 to 4 minutes on each side, until mostly golden brown. Cool and drain on paper towel lined plate.

Place packets onto medium-high heat grill and cook for 15-18 minutes per side, or until all ingredients reach an internal temperature of 165°.

After all the arepas are made, increase heat to medium-high and add corn, zucchini, red onion and jalapeño to the pan. Season with remaining kosher salt and pepper. Sauté 4 to 5 minutes, until corn makes a popping sound and is slightly caramelized. Squeeze lime over corn.

Cut arepas in half and place on a parchment-lined, rimmed baking sheet. Top with cheese and about 1/4 cup of the corn mixture. Place in oven until the cheese is melted, about 3 minutes.