Peel the yuca and cut into 1 1/2-inch (3.8 cm) thick pieces.
Place the yuca pieces in a large pot, add about 2 quarts (2 liters) of water and 1 1/2 teaspoons salt, and boil over medium heat until very tender, about 10–15 minutes.
Drain the yuca, remove the central fibrous nerve from each piece, and mash the flesh until smooth with no lumps.
Mix in the 3 egg yolks, 3 tablespoons salted butter, 1 tablespoon minced parsley, and 2 teaspoons garlic powder (if using). Stir until evenly combined, then let the mixture cool to room temperature so it firms up.
Cover your hands with vegetable oil to prevent sticking. Place about 1.5 teaspoons of the yuca mixture in your palm and flatten it.
Put a diced Gouda cube in the center of the flattened yuca, then wrap and seal the yuca around the cheese so no cheese is exposed.
Place each ball into a mini-muffin tray or mini paper cup and freeze the formed balls for 1 hour to set.
Preheat the oven to its highest temperature (or use the broiler if available). Bake the frozen balls on the tray until they turn a light golden color.
Let the balls cool for a few minutes before serving.