First of all, put the flour, yeast, sugar and 1 tsp salt in a large bowl and mix together to combine.
In a large jug, mix together 300ml lukewarm milk and the butter. Make a well in the flour mixture and pour in the milk, mixing together to form a rough dough.
Tip out onto a floured work surface and knead for 10-15 mins or until smooth and elastic.
Put the dough in a lightly oiled bowl, cover with oiled cling film and set aside until doubled in size, about 1hr. You can leave to prove the dough in the fridge over night. It will take about 8 hrs to rise, but it will also improve flavour.
Once risen, knock out the air bubbles in the dough and divide into 8-12 equal pieces, depending on how large you want your pretzels to be.
Using your hands, roll each piece into a long rope about 30 cm long. Make sure you stretch the dough from the middle, otherwise the gluten in the dough will fight you back.
To form into pretzels, lay the rope in a U-shape with the curve pointing towards you. Take the two ends and cross them over.
Take the ends, lift them backwards and press them into the curve of the U-shape. Repeat with the remaining dough.
Heat your oven to 180C/160C fan/gas 5.
Carefully place the pretzels on a baking tray lined with baking parchment and lightly greased with oil.
Cover lightly with oiled cling film. Set aside for about 20 mins until puffy (but not fully risen like bread dough).
Fill a heatproof bowl with a boiling water and dissolve the bicarbonate of soda in. I've used 3 tablespoons of baking soda, but I know other people use a little less.
One at a time, carefully lift the pretzels and dip them in the soda solution. repeat with all and place them back to the baking tray.
Once you have them all dipped in the baking soda solution and back on the trays, place them straight into your preheated oven.
Bake in the oven for 15-20 mins or until a golden brown. Once baked, brush them with some more melted butter and dip them into the cinnamon sugar. Allow to cool on a wire rack and serve with your best coffee!