Cook the potatoes and sweet potatoes in salted, boiling water for 20-25 minutes, until they're fork tender. Drain them thoroughly.

Using a ricer, push the hot potatoes through the smallest setting (if yours is adjustible like mine).

Once all the potatoes have been riced, add 1/2 teaspoon of salt, and 1/2 cup of masarepa. Stir to combine and set it aside for 15 minutes, while you prepare the filling.

To make the filling, saute the beef with 1 tablespoon of canola oil, 1/4 cup of sofrito, 1 teaspoon of Adobo seasoning, 1/2 packet of Sazon seasoning, 1/4 teaspoon of dried oregano and 1/4 teaspoon of black pepper. Cook until the beef is no longer pink. Set the mixture aside.

To form the rellenos, use a regular sized ice cream scoop, and plop a ball of the potato mixture into your hand.

Use your free hand to pat the mixture into a disc, that's just slightly bigger than your palm, and about 1/2" thick.

Add a heaping tablespoon of the ground beef mixture into the center of the disc. Slowly cup your hand to wrap the potato mixture around the filling. Work slowly and gently to close up the fritter and form a ball.

Once the relleno is formed, roll it in some of the masarepa, so it's evenly coated with a nice cornmeal crust. Refrigerate the rellenos for 15-20 minutes, to allow them to firm up.

Fry the rellenos in canola oil that's been heated to 375-400 degrees F, for about 5-7 minutes. Allow them to cool for 5 minutes before serving.