Cut avocados in half, remove pits, and scoop flesh into mixing bowl.
Mash avocados with fork, leaving some chunks for texture.
Add diced red onion, cilantro, jalapeño, and garlic powder.
Add lime juice, salt, cumin, and coriander (if using).
Gently fold all ingredients until well combined.
Taste and adjust seasoning with additional salt or lime juice if needed.
Let rest 15 minutes before serving for best flavor.