Heat olive oil in a large pan over medium heat.
Add onion and garlic and sauté until fragrant.
Add ground beef and cook until browned.
Stir in tomato, tomato paste, spices, salt, and pepper.
Pour in water or stock and simmer for 10–15 minutes until thickened.
Mash avocados in a bowl and mix with lime juice, tomato, onion, salt, and coriander.
Whisk all creamy sauce ingredients until smooth and chill.
Warm taco shells according to package instructions.
Fill shells with ground beef, top with cheese, guacamole, and coriander.
Drizzle with creamy taco sauce or serve on the side.