In a large bowl, combine the tomatoes, onion, cilantro, lime juice and a big pinch of salt and pepper. Set aside - don’t add the avocado until right before serving.
Heat the butter in a large skillet over medium-low heat. Whisk together the eggs, cream and a big pinch of salt and pepper until combined. Whisk in the green onions. Swirl the melted butter around the pan.
Pour the eggs in the skillet. Push gently with a spatula often, until the eggs are cooked to your desired liking. Transfer them to a plate or bowl.
Keep the same skillet over medium heat. To make the tacos, sprinkle ½ ounce of cheddar in the skillet, roughly the same size as your tortilla. It should start to melt right away. Place your tortilla directly on top of the cheese.
Add another ½ ounce of cheese to the tortilla. Top with the scrambled eggs. Let the tortilla cook until the cheese is golden and getting crisp on the outside edges.
Add a sprinkle of the pico de gallo to the scrambled eggs. Or you can use it as topping.
Fold the tortilla in half. Transfer from the skillet with a spatula to a plate. Serve with more of the pico and a squeeze of lime.