Preheat oven to 450 degrees.
Bring 4 quart pot of water to boil, salt to taste.
Coat a 13x9x3" Lasagna Baking Dish with non-stick spray.

To small bowl add olive oil, 2 tsp salt, 2 tsp pepper, juice from 1 lemon, and garlic.
Mix until well combined, set aside.

In another bowl combine parsley, dill, and chives.
Toss to well combine, set aside.

Thinly slice 1 lemon, set aside.
Thickly slice 1 lemon, set aside.

Place salmon into a medium bowl and add 1/3 of the olive oil/garlic mixture.
Top with a few large pinches of herb mixture.
Toss and rub salmon until it is fully covered with herbs and olive oil/garlic.
Set aside.

In a large bowl, combine brussels sprouts, onion, remaining olive oil/garlic mixture, and 2/3 of remaining herbs.
Toss so that everything is well coated.
Pour into Lasagna Baking dish.

Add Farro to boiling water (boil 30 minutes).

Place baking dish with brussels sprouts into oven.
Bake for 9 minutes then stir and bake for another 9 minutes (18 minutes combined)

Remove baking dish from oven, clear openings in center and add salmon.
Place lemon slices on salmon and add remaining lemon to dish.
Place back in oven and bake for 12 minutes.

Strain Farro and discard the water.
Add Farro back to the pot, stir in butter and remaining herbs.

Serve salmon on top of farro and brussels sprouts.