Preheat the oven broiler on low.

Make the Guacamole: Mash the avocado in a bowl with a fork until smooth. Mix in the garlic powder, ground cumin, lime juice, and chopped cilantro. Season with salt and pepper to taste. Cover and refrigerate until ready to serve.

Cook the Beef: Heat a nonstick pan over medium heat. Once hot, add the ground beef, onion powder, cumin, garlic powder, paprika, and chili powder.

Break up the beef into smaller pieces with a spatula and cook until no longer pink. Drain any excess grease. Season with salt and pepper. Bring to a low simmer, stirring occasionally.

Heat the Refried Beans: In a small nonstick pan over low heat, stir the refried beans occasionally until hot.

Place the tortilla chips on a baking sheet. Spoon the beef over the tortilla chips; top with all the cheeses. Broil until the cheese has melted.

Mix the sparkling water and lemon slices. Serve over ice if desired.

Serve: Remove nachos from the oven and top with refried beans, lettuce, tomato, jalapeño (if using), onion, sour cream, and guacamole. Enjoy with lemon sparkling water.