Whisk the eggs, cream or milk, and water together in a medium bowl
Heat the oil in a large skillet over medium-high heat
Add the onions and jalapeño pepper and cook, stirring, until the onion is soft and starts to brown, about 3 minutes
Add the garlic, cumin, salt, and pepper and cook, stirring, for 30 seconds
Lower the heat to medium-low, add the eggs, and cook, stirring occasionally until almost set, about 5 minutes
Crumble the tortilla chips into the mixture, add the cheese and salsa, and continue to cook, stirring, until the eggs are fully cooked to your liking
Serve sprinkled with tomatoes and topped with avocado slices and cilantro. Serve extra chips and salsa on the side
