Spinach Stuffed Flounder
Light, elegant, and forgiving — that’s how I describe this Spinach Stuffed Flounder. It’s the kind of dinner that looks like you spent an hour fussing but really comes together in under 30 minutes of active work. The filling is creamy and bright, the flounder rolls up neatly, and the finishing brush of olive oil and Old Bay gives it a restaurant feel without a restaurant price tag.
I make this when I want something special without a long grocery list. The cheeses hold the spinach together so the rolls stay intact while baking, and the Old Bay adds a familiar, briny lift that pairs naturally with delicate white fish. If you’re feeding company or just treating yourself, this recipe scales cleanly.
Read through the notes and tips before you start — a couple of small technique points (how to shape the filling, how to roll the fillets seam-side down) will keep things tidy and consistent. Now let’s get into the components and the straightforward step-by-step so you can get dinner on the table with confidence.
Ingredient Rundown
- 6 flounder fillets, about 4–6 oz each, boneless & skinless — the main protein; thin fillets roll easily and cook quickly.
- ½ tsp. Old Bay Seasoning or to taste — provides the savory, slightly spicy seafood-friendly seasoning.
- 1 tbsp. olive oil — brushed over the tops to help browning and keep the fish moist.
- 3 oz. cream cheese, softened — binds the stuffing and gives a creamy texture.
- ½ cup mozzarella cheese, shredded — adds mild melt and stretch to the filling.
- ½ cup feta cheese, crumbled — delivers tang and salt to balance the cream cheese.
- 3 oz. baby spinach, roughly chopped — the green element; chop roughly so it distributes evenly in the filling.
From Start to Finish: Spinach Stuffed Flounder
- Preheat the oven to 350°F.
- In a large mixing bowl combine 3 oz softened cream cheese, ½ cup shredded mozzarella, ½ cup crumbled feta, and 3 oz roughly chopped baby spinach. Mix with your hands or a spatula until thoroughly combined and paste-like. Set the mixture aside.
- Pat the 6 flounder fillets dry with paper towels and lay them flat on a large board. Measure the ½ tsp Old Bay seasoning and divide it in half.
- Sprinkle half of the Old Bay (about ¼ tsp total) evenly over the surface of the fillets.
- Divide the spinach-cheese mixture into 6 equal portions. Working with one fillet at a time, shape a portion of the stuffing into an oval/egg shape, place it near the tail end of the fillet, then roll the fillet up from the tail toward the head jelly-roll style. Place each rolled fillet seam side down in a single layer in a baking dish.
- Sprinkle the remaining half of the Old Bay (about ¼ tsp) evenly over the tops of the rolled fillets. Using a pastry brush or spoon, brush the 1 tbsp olive oil evenly over the tops.
- Bake in the preheated oven for about 20 minutes, until the fish is opaque and flakes easily with a fork.
Why This Recipe Belongs in Your Rotation
This Spinach Stuffed Flounder checks a lot of boxes: it’s fast, low-effort, elegant to serve, and uses pantry-friendly items you probably have or can keep on hand. The technique is repeatable — once you shape the filling and roll the fillets a couple of times, they go together quickly.
It sits in a sweet spot between weeknight simplicity and weekender presentation. If you want a light main without sacrificing flavor, this does the job. And because the filing is rich but not heavy, it pairs well with simple sides — roasted or steamed vegetables, a simple grain, or a crisp salad.
Low-Carb/Keto Alternatives
Good news: this recipe is already very low in carbs. The filling is cheese- and spinach-based with no breading, so it fits naturally into a low-carb or keto plan. If you’re tracking strict macros, the primary sources of calories here are the cheeses and the fish — both are keto-friendly.
If you want to trim carbs even further, focus on side choices: serve the rolls with leafy greens or roasted non-starchy vegetables instead of grains or starchy sides.
Equipment & Tools
- Large mixing bowl — to combine the cheeses and spinach.
- Cutting board and sharp knife — to pat and arrange fillets and to roughly chop the spinach if needed.
- Paper towels — for drying the fillets; dryness helps the seasoning stick and reduces splatter.
- Baking dish — just big enough to hold the rolls in a single layer so they cook evenly.
- Pastry brush or spoon — to brush the olive oil over the tops before baking.
- Measuring spoons and cups — to portion the cheeses and Old Bay accurately.
- Oven mitts and fork — for finishing checks and safe handling.
Steer Clear of These
- Don’t leave wet spinach in the filling. Excess moisture will make the filling loose and the rolls soggy. Use the stated 3 oz roughly chopped baby spinach and press out any excess water before adding to the cheeses.
- Don’t overstuff the fillets. If the filling is too large for the fillet, the roll won’t seal neatly and may open while baking. Divide the mixture into 6 equal portions as instructed.
- Don’t skip drying the fillets. Pat them dry so the Old Bay adheres and the rolls hold their shape.
- Don’t crowd the baking dish. Arrange the rolls seam-side down in a single layer for even cooking and neat presentation.
- Don’t assume baking time is exact for all ovens. Start checking at 18 minutes if your oven runs hot; look for opaque flesh that flakes with a fork.
Nutrition-Minded Tweaks
If you want to nudge this recipe toward a lighter plate without inventing new components, small adjustments work well:
- Reduce the mozzarella by a tablespoon or two if you want slightly fewer calories while keeping the melty texture.
- Divide the cream cheese across the portions evenly — ensure you stick to the 3 oz called for to keep the filling cohesive; going lighter on cream cheese and a touch heavier on the spinach (within the existing ingredient) will cut calories slightly.
- Mind portion sizes. Serving one fillet per person with a large salad or steamed greens keeps the meal balanced without extra changes to the recipe.
Pro Tips & Notes
Prep & timing
Soften the cream cheese before you start. It mixes far more easily and you’ll get a uniform paste without overworking the filling. If the cream cheese is too cold, the mixture stays lumpy and is harder to shape into ovals.
Shaping & rolling
Shape the stuffing into an oval or egg shape no wider than the fillet near the tail. That helps the roll maintain a smooth profile when you roll toward the head. Roll firmly but not tightly — the roll should close around the filling without squeezing it out.
Seasoning
The recipe’s Old Bay measure is modest on purpose. It seasons the fish and top, so distribute it as directed — a little on the inside surface and a little on top. That layered approach is more balanced than dumping it all in one place.
Baking checks
Flounder is thin and cooks quickly; check it at 18 minutes if you have a fast oven. The fish should be opaque through and flake when you test the middle with a fork. If you prefer a slightly browned top, you can move it under the broiler for 30–60 seconds — watch it closely.
How to Store & Reheat
Cool the rolls to room temperature before storing. Place them in an airtight container and refrigerate for up to 3 days. For longer storage, freeze them on a tray until firm, then transfer to a freezer-safe bag for up to 1 month. Thaw in the refrigerator before reheating.
To reheat, cover the rolls with foil and bake at 325°F until warmed through (about 10–15 minutes from chilled). Microwaving will work in a pinch but can make the fish rubbery; if you must microwave, do short intervals and finish in a warm oven for best texture.
Top Questions & Answers
- Can I prepare the filling ahead? Yes — you can make the cheese-spinach mixture and keep it refrigerated for up to 24 hours before assembling. That speeds assembly on the day you plan to bake.
- What if my fillets are larger or smaller than 4–6 oz? Adjust the portion of filling accordingly. If the fillet is much smaller, use slightly less filling to avoid overstuffing; if much larger, you can either make a bit more filling from the same ratios or accept a looser roll.
- Can I skip the Old Bay? The recipe uses it for a reason — it’s a concise seafood seasoning — but you can omit it if needed. The rolls will still be flavorful because of the cheeses and spinach.
- How do I know when the fish is done? It should be opaque and flake easily with a fork. Because fillets vary in thickness, visual checks and a gentle flake test are your best indicators.
The Takeaway
Spinach Stuffed Flounder is an uncomplicated dish that punches above its weight in flavor and presentation. With a creamy cheese-spinach filling, a light dusting of Old Bay, and a quick bake, you get a weeknight-friendly main that’s elegant enough for guests. Follow the small technique points — dry the fillets, portion the filling, and lay the rolls seam-side down — and you’ll have a reliable, repeatable dish that becomes a staple in your dinner rotation.
Spinach Stuffed Flounder
Ingredients
Equipment
Method
- Preheat the oven to 350°F.
- In a large mixing bowl combine 3 oz softened cream cheese, ½ cup shredded mozzarella, ½ cup crumbled feta, and 3 oz roughly chopped baby spinach. Mix with your hands or a spatula until thoroughly combined and paste-like. Set the mixture aside.
- Pat the 6 flounder fillets dry with paper towels and lay them flat on a large board. Measure the ½ tsp Old Bay seasoning and divide it in half.
- Sprinkle half of the Old Bay (about ¼ tsp total) evenly over the surface of the fillets.
- Divide the spinach-cheese mixture into 6 equal portions. Working with one fillet at a time, shape a portion of the stuffing into an oval/egg shape, place it near the tail end of the fillet, then roll the fillet up from the tail toward the head jelly-roll style. Place each rolled fillet seam side down in a single layer in a baking dish.
- Sprinkle the remaining half of the Old Bay (about ¼ tsp) evenly over the tops of the rolled fillets. Using a pastry brush or spoon, brush the 1 tbsp olive oil evenly over the tops.
- Bake in the preheated oven for about 20 minutes, until the fish is opaque and flakes easily with a fork.
Notes
Check forpin bonesbefore stuffing
Don’t overfill — some stuffing should stay inside the roll
Fresh baby spinach is softer than frozen
If using frozen fish,thaw and pat dryfully
Add crab meat🦀 for a seafood-restaurant upgrade
Breadcrumb toppingfor a golden, crunchy crust
Fresh herbslike dill, parsley, or chives in the filling
Lemon zestor a squeeze of lemon for brightness
Cayenne or black pepperfor heat
