In a medium bowl, stir together cheese, corn, cilantro, salt, and pepper.
Line a tortilla press with plastic wrap.
Divide Masa Empanada Dough into 15 portions (about ¼ cup or 64 grams each). Using prepared tortilla press, press each portion flat. Spoon about 3 tablespoons (19 grams) cheese mixture into center of each dough piece; fold dough in half until edges meet. Crimp edges as desired. Cover and refrigerate.
In a large Dutch oven, pour oil to a depth of 3 inches, and heat over medium-high heat until a deep-fry thermometer registers 350°F (180°C) to 360°F (182°C).
5.Working in batches, carefully add empanadas to hot oil. Fry, turning occasionally, until golden and crisp, 3 to 5 minutes. Remove using a slotted spoon or spider strainer, and let drain on paper towels. Serve with sour cream and cilantro.