Here’s how to make a soft, moist fish omelette using leftover fish, eggs, butter, cilantro, onions, and avocado. It’s high in protein, easy to make, and a great way to start your day.

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I usually make extra dinner so I have something ready for the morning.
This morning, I used leftover blackened swordfish to make a quick breakfast omelette.
Fish is a great addition to any omelette. Use what you’ve got. Use up your snapper, mahi mahi, grunts, shrimp, what ever you cooked last night and add to your omelet!
Smoked salmon or a packaged salmon loin works too and it’s already cooked.
Omelette Flavor Options
Cajun Flavor: Blackened fish with south-of-the-border flavors including cilantro, onion, and lime.
Summer Omelette: For a summer flavor combo, try cooked or smoked salmon with fresh dill, red onions, and a dollop of whipped cream cheese.
Mediterranean Style: Use cooked white fish, chopped tomatoes, olives, and crumbled feta. Finish with a pinch of oregano.
Scallion & Soy: Use cooked flaked white fish or shrimp with chopped scallions and a splash of coconut aminos or tamari soy sauce. Garnish with toasted sesame seeds.
Potato & Pepper: Mix in cooked diced potatoes, sautéed bell peppers, and mild white fish. Top with a sprinkle of sweet paprika.

Ingredients
Makes 1 omelette
- Cooked fish
- Eggs
- Salt and pepper
- Butter
- Cilantro
- Red onion
- Avocado
Visit Key West Fish Recipes for a full list of our fish recipes.
TIP: Omelettes take a few minutes to make so have all of your ingredients lined up before you turn on the stove.
How To Make a Fish Omelette
- Fish: I'm using leftover cooked roasted swordfish recipe in this omelet. I brushed this fish with melted butter, seasoned with blackened seasoning in a pre-heated 400°F oven for 15 minutes. Chop the fish into bite size pieces before you begin.
- Veggies and Fruits: Chop the cilantro and onions, slice the avocado, and sprinkle it with lime juice to keep it fresh. Get everything prepped before you start cooking. You can also use other vegetables like bell peppers, tomatoes, spinach, or cooked potatoes.

- Cut the cooked fish into bite-sized pieces and chop the cilantro, onions, avocado and lime.
- Heat a small nonstick skillet over medium heat and melt a little butter. Add the cooked fish and onions and cook for about a minute to heat. Transfer to a plate and wipe out the skillet with a paper towel.
- While the fish is heating up, crack the eggs into a bowl, add a little salt and pepper and beat them with a fork.
Add a tablespoon of butter to the skillet. Tilt the pan so the butter coats the surface. - Pour in the eggs and let them sit undisturbed for about 30 seconds. Use a spatula to gently lift the edges as they set, letting the uncooked eggs run underneath. Keep lifting and tilting the pan so the eggs cook evenly. When they’re almost set, add the warm fish and chopped cilantro.
- Fold the omelette in half and cook for another minute until the eggs are fully cooked. Slide onto a plate and enjoy with avocado slices.
Note: I topped this omelette with taco sauce that I had leftover from last night's swordfish tacos. The recipe is in the notes on the printable recipe card.

High Protein Sides
While an egg only has 6g of protein, four ounces of cooked swordfish has about 20 grams of protein.
Here are some suggestions to add more protein to your breakfast eggs:
- Sliced avocado: 3 grams of protein. It’s not a big protein source, but it adds healthy fats and fiber to keep you full.
- Cottage cheese: A half-cup of low-fat cottage cheese has about 14 grams of protein.
- Turkey sausage – Two small turkey sausage links have about 10–12 grams of protein
- Steak – Two ounces has about 14–16 grams of protein.
Seafood Dinner Recipes
Cooking in the Keys is a food blog from Key Largo, Florida. Try our fresh caught yellowtail snapper, mahi mahi with cream sauce, pan-fried grouper cheeks, and spiny lobsters!
For more fish and shellfish recipes, visit our recipe index.

Fish Omelette Recipe
Ingredients
- ¼ cup chopped cooked fish
- 2 large eggs
- salt and pepper to taste
- 1 tablesppon butter
- 2 tablespoons chopped fresh cilantro
- 2 tablespoons diced red onion
- ½ avocado, sliced
Instructions
- Cut the fish into bite-sized pieces and chop the cilantro, onions, avocado and lime.
- Crack the eggs into a bowl, add a little salt and pepper and beat them with a fork until the whites are broken down.
- Heat a small nonstick skillet over medium heat and melt a little butter. Add the cooked fish and onions and cook for about a minute to heat. Transfer to a plate and wipe out the skillet with a paper towel.
- Add a tablespoon of butter to the skillet. Tilt the pan so the butter coats the surface.
- Pour in the eggs into the pan and let them sit undisturbed for about 30 seconds. Use a spatula to gently lift the edges as they set, letting the uncooked eggs run underneath. Keep lifting and tilting the pan so the eggs cook evenly. When they’re almost set, add the warm fish and chopped cilantro.
- Fold the omelette in half and cook for another minute until the eggs are fully cooked. Slide onto a plate and enjoy with avocado slices.
Felice Kaufman says
I’ll be making this fish omelet tomorrow with leftover swordfish. Perfect timing!