Maczanka krakowska (Kraków-style gravy-soaked pork sandwich)

Start the semi-fermented dill cucumbers at least 2 days before you want to make the dish. Place the cucumbers, garlic, dill and horseradish into a sterilised jar or container

Dissolve the salt in the warm water to create a light brine. Pour the brine over the vegetables in the jar until the cucumbers are fully submerged. Cover the top loosely with a muslin cloth (or leave the lid ajar) and leave in a cool, dark place at room temperature for 2-3 days

Once lightly fermented, slightly sour and still crisp, refrigerate until required

For the braised pork collar, preheat the oven to 150°C

Season the pork generously with salt and pepper. Heat the oil in a heavy-based ovenproof pan or casserole dish over a medium-high heat. Sear the pork on all sides until deeply golden brown. Remove and set aside

Turn the heat down to low, add the sliced onions to the pan and cook slowly for 15-20 minutes until soft and golden brown

Add the garlic, paprika, caraway seeds and black pepper and cook for 1 minute until fragrant. Return the pork to the pan and add the bay leaves, stock and marjoram

Bring to a gentle simmer, then cover and braise in the oven for 2½-3 hours, or until the meat is fork-tender

For the dough for the Kaiser rolls, combine the flour, salt, yeast and sugar in a stand mixer fitted with a dough hook attachment. Add the butter and water and mix until it forms a dough, then knead for 8-10 minutes until smooth and elastic

Cover and leave to rise until doubled in size, about 1-1½ hours depending on the temperature of your kitchen

Line 2 baking sheets with baking paper

Once the dough has risen, divide it into 10 equal pieces. To shape the dough into the traditional Kaiser roll shape, roll a piece of dough into a long sausage and loosely tie a knot in the middle, leaving a hole in the middle. Fold the ends into the hole and tuck underneath. Place onto one of the baking sheets and repeat with the remaining pieces – leave a little space in between each roll

Cover and prove the rolls for 30-40 minutes at room temperature

Once the pork is cooked, remove from the oven and increase the heat to 220°C

Remove the pork from the liquor (keep it warm) whilst you transfer the braising liquid and onions into a blender. Blend until smooth (you may have to work in batches), then return to the pan

Lightly brush the rolls with water and sprinkle with poppy seeds. Bake for 15-18 minutes until a deep golden brown and cooked through, then remove to a wire rack to cool slightly

Reduce the liquor over a medium heat to a rich gravy consistency. Adjust the seasoning

Slice the Kaiser rolls in half and dip into the gravy, leaving for 1 minute to let the gravy soak into the bread (you want them to be completely soaked)

Meanwhile, slice or shred the pork and dress it with a little of the gravy. Drain and slice some semi-fermented dill pickles

To build the maczanki, spread some Polish Sarepska mustard onto the gravy-soaked bun bases. Top with the shredded dressed pork, a little more gravy, then top with the gravy-soaked bun lids. Serve with more gravy and the pickles on the side