Landry'S Pontchartrain Sauce - cooking recipe

Ingredients

1 small onion, peeled and chopped fine
1 cup Chardonnay wine
1 tablespoon butter (no substitutions)
1 tablespoon flour
1 cup fish stock or 1 cup chicken stock
1/4 cup mushroom, chopped fine
1 small green pepper, seeded and chopped fine
2 garlic cloves, minced
1/2 cup butter, chopped into 1 tablespoon pieces (no substitutions)
cayenne pepper or tarragon

Preparation

Cook the Chardonnay and the onion together over a low fire until the wine is reduced and the onion is very soft and transparent.
Melt 1 tablespoon of butter in another heavy saucepan over medium heat.
Add the flour and whisk until blended.
Add the stock a little at a time, whisking constantly until blended and thickened.
Add the mushrooms, green pepper and garlic. Cover and simmer down until the vegetables are soft.
Remove from heat and add 1/2 cup of butter pieces until melted.
Add to the Chardonnay (which should now be reduced to a glaze) mixture.
Blend well over very low heat.
Season to taste with salt (may not be needed), black pepper, cayenne, and tarragon.