Prep all ingredients according to the ingredient list.
Heat extra-virgin olive oil in a skillet over medium heat. Add the ground beef, chili powder, ground cumin, garlic powder, and black pepper. Sauté, breaking it into small pieces, until fully browned. Remove from heat.
Warm the soft taco shells in a pan over medium heat until pliable on both sides.
Fill the taco shells with the cooked beef. Top with diced onion, diced tomatoes, shredded Monterey Jack cheese, and lettuce.
In a bowl, mash the avocado until smooth. Add fresh cilantro, lime juice, garlic powder, cumin, and black pepper. Stir until well combined.
Combine lemon, chia seeds, and sparkling water. Stir well and let sit until the chia seeds bloom.
Serve the tacos with tortilla chips and guacamole alongside lemon chia sparkling water.