Chop asparagus spears into about 1-inch chunks. Discard the tough wooden bottoms of the spears. Slice the red onion thin and scramble the eggs with the milk (or cream).
In a large skillet, add a drizzle of oil over medium heat. Then add asparagus, onion, and a pinch of salt and pepper. Cook until the veggies are slightly soft, about 4 minutes.
Add the butter to the pan and pour in the scrambled eggs and let sit for a few minutes. Once the eggs start to firm up, turn the heat down to low and slowly stir them so they scramble a bit. Cook the eggs until they are almost cooked through, but still a tiny bit liquid. Be careful not to over cook the eggs.
When the eggs are almost done, add in flaked salmon, goat cheese, scallions, and capers and carefully fold those into the eggs. Try to keep the salmon in nice big chunks. Cook for just a minute to gently warm ingredients.
Season the eggs with salt and pepper and serve the eggs with toast, extra scallions, and capers.