Wash and trim all asparagus spears (snap off the tough bottom ends where they naturally break). Place into a steamer basket and steam on medium-high for about 5 minutes, until tender-crisp - do not overcook!
Once steamed, remove about half the asparagus and place it into a blender. Add ½ cup / 125ml of the steaming water, olive oil, tarragon, capers, lemon zest and juice, mustard, and salt. Blend on high until completely smooth (add more steaming water if necessary / desired). Taste and adjust seasoning.
Spoon your desired amount of sauce onto a serving dish. Give the remaining asparagus a drizzle of olive oil, toss, and place on top of the sauce. Add chives and tarragon, and flaky salt.
Say thank you and enjoy immediately.
