Pat salmon filets dry and season with old bay and lemon pepper seasoning, drizzle with olive oil to adhere the seasoning to the fish and massage
Make a slit in the center of the salmon using a pairing knife being sure not to cut all the way through to the other side of the salmon
Set salmon aside and work on filling
To a small bowl, add room temperature cream cheese, Italian cheese, parmesan and season with old bay
In a skillet, saute onion and spinach for 2 minutes or until slightly softened and fragrant
Add spinach and onion mixture to the cream cheese and stir well to combine
Divide mixture into even portions and use a spoon to fill the salmon being sure not to over stuff
In the skillet, on medium heat, add oil and sear salmon presentation side down for 3 minutes or until golden brown and slightly blackened
Flip salmon and add butter, thyme and garlic
Baste the salmon filets with the butter mixture for 2 minutes or until salmon reaches desired temperature of 145 or greater
Remove salmon and work on sauce
On medium low heat, add soy sauce, mirin, oyster sauce and butter and stir to combine
Sauce is done when it's glossy and semi thick
Pour sauce over salmon filets and enjoy