In a medium bowl, crack the eggs and whisk until just combined. Season with a pinch of salt and pepper.

Heat a large non-stick skillet over medium heat. Add butter or oil and allow it to melt and coat the pan.

Add the diced onion and sauté for 1-2 minutes until translucent but not browned.

Add the minced jalapeño and cook for another 30 seconds.

Add the diced tomatoes and cook for 1-2 minutes until they begin to soften and release some juice.

Pour the beaten eggs into the pan and let them set for about 30 seconds.

Using a wooden spoon or silicone spatula, gently pull the edges toward the center, allowing uncooked egg to flow to the edges.

Continue this gentle folding motion until eggs are almost set but still appear slightly moist, about 2-3 minutes.

Remove from heat, sprinkle with fresh cilantro, and fold it in gently.

Taste and adjust seasoning with additional salt and pepper if needed.

Serve immediately with warm tortillas if desired.