In a large bowl or a bowl of a standing mixer, whisk flour with sugar, cinnamon and active dry yeast.If using a standing mixer, fit it with the hook attachment.
Add warm water and knead on low for 5 minutes.
Add salt and butter, knead on medium until the dough is soft and smooth (for about 10 minutes).
Knead dough by hand a couple of times and shape into a smooth ball. Place into a lightly greased bowl, cover with a towel and let rest for 40 minutes or until doubled in size.
Preheat oven to 200 degrees C. (400F).
Once dough is done resting, cut it into 8 equal pieces. Roll each section into a long rope about 30 cm long.
Cut the dough into 2cm (one inch) pieces to make the pretzel bites.
Combine the boiling water and baking soda, stirring until the soda is totally (or almost totally) dissolved. Set the mixture aside to cool to lukewarm (or cooler).
Put the pretzel bites in the water solution in batches. (about 10 bites at a time). Leave for about 1 min.
Place pretzel bites on a lined baking sheet. Make sure they are not touching.
Brush the tops with egg wash or plant milk.
Place into the oven and bake for 11-13 minutes until golden brown.
Let cool down completely, brush with melted butter and dip into cinnamon sugar.