01 - Preheat oven to 350°F. Arrange taco shells on baking sheet and warm for 5 minutes until crisp.
02 - Heat large skillet over medium-high heat. Add ground beef and cook, breaking up with spoon, until browned, about 5-6 minutes.
03 - Add chopped onion to skillet and sauté until softened, about 2 minutes. Stir in garlic and cook 30 seconds.
04 - Sprinkle taco seasoning and tomato paste over beef. Mix well. Pour in water, reduce heat to medium, and simmer 4-5 minutes until thickened.
05 - Remove shells from oven. Spoon beef mixture evenly into each shell.
06 - Top with lettuce, cheese, tomato, sour cream, cilantro, jalapeño, and salsa as desired. Serve immediately with lime wedges.