Dinner

Homemade Fish Finger Sandwich with Sweet Potato Chips and Tartar Sauce Recipe

ByLuna Ryder January 12, 2026January 12, 2026

Introduction

Enjoy a delicious homemade fish finger sarnie that’s crispy on the outside and tender inside. Paired perfectly with sweet potato chips and a zesty tartare sauce, this sandwich is a fresh twist on a classic favorite.

A sandwich on a white plate with a white marbled texture background. The sandwich has three layers: the top is a light brown, soft bun with some white creamy sauce on it, the middle layer is a thick, crispy golden-brown patty with a rough texture, and the bottom layer is fresh green leafy arugula on a darker brown bun base. Next to the sandwich, there are thick, orange-brown sweet potato fries and a wedge of bright yellow lemon. In the background, a blurred bowl with white creamy sauce and a spoon is visible. Photo taken with an iphone --ar 4:5 --v 7

Ingredients

300g skinless white fish fillet
1 large egg, beaten
50g cornflakes, blitzed or bashed into crumbs
3 sweet potatoes, cut into chunky chips
1 tbsp olive oil
4 small wholemeal buns
Small handful mixed salad leaves
1 lemon, cut into wedges
2 tbsp light mayonnaise
1 tbsp gherkins
1 tsp capers, rinsed and chopped

Instructions

Step 1: Heat the oven to 200°C (180°C fan)/gas mark 6. Cut the fish fillet into 4 equal-sized portions.
Step 2: Dip each fish portion into the beaten egg, then coat evenly with the crushed cornflakes. Chill the coated fish in the fridge for 10 minutes to help the coating set.
Step 3: Toss the sweet potato chunks with olive oil and seasoning, then spread them onto a baking tray. Cook in the oven for 20 minutes.
Step 4: While the chips bake, prepare the tartare sauce by mixing the light mayonnaise, chopped gherkins, capers, and a pinch of seasoning in a small bowl. Set aside.
Step 5: After 20 minutes, remove the tray, turn the sweet potato chips over, and place the fish portions on the tray. Return to the oven and cook everything for another 15 minutes. Turn the fish halfway through cooking to ensure an even crisp.
Step 6: Once cooked, lightly toast the wholemeal buns. Place a handful of salad leaves inside each bun, add a crispy fish finger, and top with a dollop of tartare sauce. Serve with the sweet potato chips and lemon wedges for squeezing over.

Tips & Variations

For extra crunch, double coat the fish by dipping twice in egg and cornflakes.
Use gluten-free cornflakes and buns if you need a gluten-free option.
Add a slice of tomato or cucumber inside the sandwich for extra freshness.
Try swapping sweet potato chips for regular oven chips or a side salad.

Storage

Store any leftover fish fingers and sweet potato chips in an airtight container in the refrigerator for up to 2 days. Reheat in a hot oven or air fryer to maintain crispiness. Avoid microwaving, as this can make the coating soggy.

How to Serve

A sandwich is placed on a white plate against a white marbled background. The sandwich has four main layers: the bottom layer is a soft brown bun with visible texture, followed by fresh green arugula leaves. On top of the greens is a thick, golden crispy patty with a crunchy texture. The top layer is a dollop of white creamy sauce with small pieces inside, under a matching brown bun. Next to the sandwich are thick, orange-brown baked sweet potato fries. There are two lemon wedges placed on the plate beside the sandwich. Photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use frozen fish fillets for this recipe?

Yes, you can use frozen skinless white fish fillets. Make sure to thaw them completely, pat dry to remove excess moisture, and proceed with the coating steps as usual.

How do I keep the fish coating crispy?

Chilling the coated fish before cooking helps the crumbs adhere better. Also, turning the fish halfway through baking ensures even crispiness. Avoid overcrowding the baking tray to allow hot air to circulate properly.