1a. Cook the onions and garlic in a little bit of oil until the onions are tender (4-5 minutes). Add the beef and cook until the beef is no longer pink (7-10 minutes). Toss in the chili powder, paprika, cumin, oregano, and adobo. Next, add tomato sauce and stir to combine.
1b. At the same time, boil the potatoes until just fork-tender.
2. Add the cooked potatoes to the meat mix and ladle about 1 cup of the water used to boil the potatoes into the mix as well. Once the water is incorporated take it off of the heat.
3. To assemble the empanadas, lay a slice of cheese in the center of the disc. Spoon 1-2 tbsps of the meat mixture onto the center and fold the disc over on itself to form a half-circle. Crimp the edges with a fork.
4. In a large pot, heat the vegetable oil (about 1 1/2" up the side of the pot) to 375 degrees. Gently place the empanada in the oil and cook on both sides until golden brown. Flipping over after about 45 seconds and then cooking the other side.