Add the red wine vinegar and red onion to a small bowl and set aside to gently pickle. (Note: This is an optional step. Feel free to skip it if you're short on time and simply serve the onions raw.)

Heat the oil in a skillet over medium heat. Add the shallot and fry for 2-3 minutes, until softened.

Stir in the garlic and spices and fry for 1 minute longer. Add the ground beef with a pinch of salt and break it apart with a wooden spoon. Cook for 8-10 minutes, until browned and no longer pink.

Turn off the heat. Arrange a bed of tortilla chips on a plate and top with the ground beef mixture. Drain the pickled onions and top the nachos with the onions, Greek yogurt, and cilantro. Serve.

Meal Prep Tip: Store the cooked beef mixture and toppings separately in airtight containers in the refrigerator. Reheat the beef mixture and assemble the nachos just before serving to keep the chips crisp.