Stir the warm water, dried yeast, salt and maple syrup. Lightly cover with cling film in a warm place to froth up (10 minutes).
Place flour in a medium bowl with 4 tbs of your chosen mustard and stir in the frothed yeast mixture. Turn dough out onto a lightly floured bench and knead until soft and pliable (about 3-5 minutes)
Place dough in a lightly oiled bowl, covered with a tea towel and allow to rise in a warm, draft-free spot until doubled in size (about an 1 hour).
Pour water (for simmering) halfway up a medium sized pot and bring to a simmer. (Start making the pretzel's whilst the water is coming to a simmer).
Divide the pretzel's into equal pieces (12 pieces for small pretzels, or 6 medium pretzels) and roll each piece into thin logs (about 1cm in diameter for the small pretzels, or 2cm for the larger ones).
Take one dough log, and grabbing the ends, cross (twist) them over each other about (5cm down the logs). Then fold down the ends to attach with the bottom of the pretzel. See this video for a instructional video on how to fold pretzels. https://www.youtube.com/watch?v=4bu8MGBvJx0
Turn the oven on to 180C and line two baking trays with baking paper. Place bicarb (baking) soda in the pot of water and stir to combine. Gently lower a few pretzels into the water and cook for 1-2 minutes (bigger pretzels may need 2-3 minutes).
Gently remove pretzels (draining them of excess water) and place on the baking tray. Allow the tops to dry slightly.
Brush tops with the extra mustard mixed with the maple syrup.
Bake pretzels for about 20 minutes until the tops are a golden brown (keep this in mind: the lighter the pretzel, the softer the pretzel and larger pretzels may need 25-30 minutes to cook fully through). Brush tops with melted vegan butter immediately once out of the oven.