Step 1

Heat the butter in a saucepan over medium-high heat until melted. Add the shallots and saute for around 4 minutes until softened (but not browned).

Step 2

Pour the champagne into the pan and increase the heat to high. Simmer until the liquid has reduced by half (around 5-8 minutes).

Step 3

Add the fish stock to the pan and bring it back to a simmer. Again, reduce by half (around 5-8 minutes).

Step 4

Stir the cream and parsley into the sauce and simmer for around 5 more minutes, until the sauce has fully combined and thickened. Season to taste.

Step 5

Serve with fish or shellfish.