1. Put the flour into the bowl of a stand mixer and add the yeast, sugar and salt. Mix well then add the water and use the dough hook on a low speed to bring it all together. Once combined, turn the speed up and knead for 10 minutes on a medium setting until you have a smooth silky dough. Transfer the dough to an oiled bowl and cover with clingfilm. Leave to rise for 1 hour or until doubled in size.
2. Knock the dough back and divide into 20 even pieces (each 40 grams). Keep the dough covered while you work with one piece at a time to shape it into a ball: pull the edges in on themselves and pinch together to make a neat ball shape. Then, push one cube of Castello Creamy Havarti into the dough ball where the seam is, and repeat pulling the edges over to make a neat ball shape. Leave to rest on a lightly oiled tray, seam side down, and covered with more clingfilm while you repeat with the rest, then leave to prove for 20 minutes.
3. Bring 2 litres of water to a rolling boil with 4 tablespoons of bicarbonate of soda. Preheat your oven to 240C or as hot as it will go. Get two large baking sheets, a slotted spoon, and the coarse sea salt to hand. Pick up one pretzel and put it onto a slotted spoon, submerge it in the boiling water and boil for 1 minute. Then remove it and place it onto a baking sheet. Sprinkle generously with coarse salt then repeat with the rest - you should be able to poach them in batches of 3 or 4.
4. Bake the pretzel bites for 8 minutes, turning the trays around halfway through cooking. If your oven doesn’t go up to 240C they might take slightly longer, so cook them for a few minutes more until they’re a deep golden brown.
Make the garlic butter
While the pretzels are baking, put the butter and garlic into a small saucepan and warm gently. Once the butter has melted, take it off the heat and stir through the finely chopped parsley. Brush melted garlic butter over the hot pretzels and serve immediately.