Begin by melting the butter in a medium sized saucepan. Add the onions and mushrooms and allow to sweat for a few minutes.
Add the garlic and stir until aromatic.
Add the cream and allow to thicken, 5 minutes. Note: If it's too thick, thin the sauce with additional cream, milk or half & half.
Add the lemon juice, white wine, Worcestershire and the spices and cook together for a few more minutes.
Now add the fish and cook together for 2-3 minutes. Note: The fish will poach in the cream sauce while it bakes.
Spoon mixture into mini cast iron skillets, rimkens or a small-ish shallow baking dish.
Top with mashed potatoes.
Cook at 350 degrees for 25 minutes. At the 25 minute point, top with cheese and turn the oven to boiler and allow the top to get golden brown.
Garnish with green onion, enjoy and cheers🥂!