Mornay Sauce for Fish

tuna steaks

Is it time for a great sauce for fish? It might be a titch too early to hit the grill, but a nice, simple mornay sauce works with so many different types of seafood, from tilapia to tuna!

That’s my grilled basil lemon tuna steak up there. It is delicious, and I never even thought I liked tuna. Why? Because I based my opinion on tuna from my experience with mushy, soggy canned tuna. Live and learn.

Tip: Don’t have arrowroot flour? Use cornstarch instead. They’re both very similar in terms of carbohydrate content (and the cornstarch is easier to find).


Mornay Sauce for Fish

4 Tbsp butter
1 Tbsp onion, finely chopped
1 Tbsp arrowroot flour
¾ cup chicken broth
1 cup cream
2 egg yolks
½ cup shredded Swiss cheese

Heat 3 Tbsp butter in saucepan. Add onion, and cook until tender. Blend in arrowroot and heat until bubbly. Gradually add broth and cream while stirring. Bring to a boil, stirring constantly. Boil 1-2 minutes. Blend 3-4 Tbsp hot mixture into egg yolks, and return to hot mixture. Add cheese and remaining butter. Serve with fish.

Yields: 6 servings

Nutritional Information per serving: Calories: 271, Carbohydrates: 2 g, Fiber: Trace, Net Carbohydrates: 2 g, Protein: 8 g, Fat: 26 g

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  1. This sounds DELICIOUS, Jamie! I love sauces on fish. Think I’ll try this soon!

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