"Dukkah" Crusted Sea Scallops with parsnips and seasonal mushrooms

Place peeled and largely chopped parsnips in a good quality thick bottomed pan and cover with 40 percent heavy cream, 40 percent milk and 20 percent water.   Cover with parchment lid and cook until soft and process through robot coup.  Use the cooking liquid to get the desired consistency.   Push through chinoise and cool.
for the mushrooms.  Pick out the best looking seasonal mushrooms and clean.  Do not wash.  If they are dirty, use a brush to clean them.
Cut to desired shapes and place aside.   Clean one bunch leeks, using the whites and the light green parts only, slice thin.  About a 6th of an inch.  Wash and dry thoroughly.   Heat some olive oil in a heavy bottomed pan and when hot add the mushrooms.   Season without moving the pan.  Once some of the moisture begins the leave the mushrooms add the leeks and lightly sautee until cooked al dente or your desired consistency.   Drain on paper towels and keep warm.
Plating; heat a small amount if the puree and place we on plate  scallops and mushrooms to follow.  Before placing the scallops on plate, lightly brush with a good olive oil and press them into the nut mixture.  For this recipe keep the Dukkah coarsly ground for texture on the scallops.  Season with fresh thyme leaves and preserved lemon or our meyer puree.
For the scallops;
Clean and lightly score/ season good quality diver sea  scallops.  Preferably u-10's.
Sear on both sides until medium rare and set aside to drain.