Sausage, leek and potato gratin with a golden bubbling crust

Recipe

Sausage, Leek and Potato Gratin

Published 09 October 2026 · Updated 10 October 2026

Pork and leek sausages sit over thin potato slices, mustard cream and thyme in a gratin that is tender underneath and browned on top. Dividing the stock between the leek base and the dish keeps the potatoes moist without making the top watery.

Not kitchen tested by The Black Farmer.
Serves 4
Prep 25 min
Cook 76 min
Total 106 min

Timing: The 25-minute prep covers slicing and arranging. The leek hob stage, sausage browning and two oven stages are sequential; resting is separate.

Ingredients

Adds 1 items across 1 products — £6.60 total.

Pantry ingredients such as oil, salt and herbs are not included.

Other Ingredients You'll Need

  • Onion — 1 medium, sliced
  • Garlic — 2 cloves, finely chopped
  • Neutral oil — 1 tbsp
  • Fine salt and black pepper — to taste
  • Leek — 1, sliced
  • Potatoes — 600g, peeled and sliced 3mm thick
  • Chicken stock — 300ml, divided: 200ml for the leek base and 100ml for the baking dish
  • Double cream — 100ml
  • Wholegrain mustard — 1 tbsp
  • Fresh thyme — 4 sprigs

Method

Make the leek base

Heat the oven to 190°C, or 170°C fan. Use a 23 x 30cm, 1.5-litre baking dish. Soften leek, onion and garlic in oil with thyme for 8 minutes. Stir in mustard and 200ml stock.

Brown the sausages

Brown the sausages in a frying pan over medium heat for 8 minutes, turning to colour all sides without cooking them through.

Layer the gratin

Arrange half the 3mm potato slices in the dish, season lightly, then spoon over the leek base. Add the remaining potatoes and pour over the cream mixed with the remaining 100ml stock. Place the sausages evenly across the top; do not bury them.

Bake covered

Cover tightly with foil and bake for 45 minutes until a knife meets only slight resistance in the potatoes.

Brown and rest

Remove the foil and bake for 15 minutes until the potatoes are tender and the sausages browned. Rest for 5 minutes.

Serving Suggestion

Serve with a sharp green salad or steamed greens.

Frequently Asked Questions

Can I assemble it ahead?

Assemble, cover and chill for up to 24 hours. Add about 10 minutes to the covered bake from cold.

How do I know the potatoes are ready?

A knife should slide through the centre without resistance before you uncover and brown the top.