Step 1

Pre-heat oven to 160°C.

Step 2

Bring brisket out of the refrigerator and let it reach room temperature (approximately 30 minutes).

Step 3

Add oil to a heavy-based, oven-safe pot and place over medium-high heat.

Step 4

Seal each side of the brisket for a few minutes to brown before removing from the pot and set aside.

Step 5

Add onion, garlic, and celery to the same pot and cook, stirring, for 4-5 minutes, or until onion is translucent.

Step 6

Stir through stock, additional mustard, and salt. Bring the liquid to a simmer.

Step 7

Return the sealed brisket back into the pot and settle amongst the vegetables and liquid.

Step 8

Seal the pot with a tight-fitting lid or foil and place in the oven for 4-5 hours, depending on the weight of your brisket (4 hours for a 1kg brisket).

Step 9

Check liquid after 2 hours, topping up with water or stock as required.

Step 10

While the brisket is cooking, pop the potatoes in a saucepan topped with cold water and bring to the boil. Simmer for ten minutes to parboil before draining. Dry the potatoes well with a clean tea towel.

Step 11

Once cooked, remove the brisket from the oven and turn the heat up to 210°C.

Step 12

Place the potatoes on a baking tray, rub with olive oil, and season with sea salt. Bake for 15-20 minutes, or until the potatoes are crispy on the outside and soft on the inside.

Step 13

Meanwhile, shred the tender brisket meat with two forks and stir it evenly through the marinade in the pot.

Step 14

Prepare coleslaw dressing by stirring together mayonnaise, yogurt, spring onions, and gherkins (if using) in a large bowl. Set aside half of the dressing to use as a drizzle for the potatoes.

Step 15

Add the coleslaw to the dressing and toss to coat.

Step 16

To serve, cut open each potato, fill with brisket, pile with coleslaw, and finish with a drizzle of coleslaw dressing, additional spring onions, and a scattering of diced gherkin.