Remove the woody ends from the asparagus by snapping the very bottom of each spear or remove the ends with a knife.
In a suitable pan place the asparagus spears and add cold water until they are just covered. Bring the water to the boil and then reduce the heat to a simmer. Cook the asparagus for 3 -5 minutes until tender – check the spears with a fork before removing.
Meanwhile, make the dressing. In a small bowl mix the yogurt and fresh herbs, zest and seasoning and mix well.
Once the asparagus is tender, turn off your stove top. Remove the pan and pour the asparagus through a strainer, being careful not to burn yourself on the pan.
Immediately, and working quickly, layer over the slices of smoked salmon.
Finish with a drizzle of yogurt dressing and olive oil and serve straight away.