if you haven't already done it, freeze 8 1/2 TBSP of the vegan butter, it should be very cold when you use it
mix the flour and the salt together
cube up the unfrozen portion of the vegan butter
drop it in the flour mix and work it until it's incorporated in the flour and the mix looks like bread crumbs
add enough of the water for the dough to come together, you may need a little more than called for
once the dough comes together roll it out on a lightly floured counter to roughly 12x6 inches with a short side facing you
grate the frozen butter over the bottom 2/3 of the dough, then fold the top down 1/2 way, then the bottom up 1/2 way, this is called the letter fold[mv_schema_meta name="How to Letter Fold Puff Pastry"]
turn the dough 90˚ and roll it out the same size as before
repeat step 7
then cover the dough tightly and chill for 20 minutes
roll the dough out to 12x6, letter fold it again, rotate, letter fold
rest 20 minutes in the fridge then repeat step 11
once this final roll out is done the dough is ready to use, chill covered tightly until you want to use it
when you're ready to bake the sausage rolls saute the onion lightly for 2-3 minutes over medium heat, add the garlic and saute another 30 seconds then remove from the heat
mix the onions and garlic with the bread crumbs and the sausage until well combined
divide the sausage evenly into 8 pieces, use a scale if you have, form the sausage into cylinders 4 inches long, and chill until ready to use
preheat the oven to 400˚ with convection or 425˚ without
[mv_schema_meta name="roll out the rough puff pastry"] to at least 12x16, trim it up to have flat sides
use a tape measure or ruler, or another flat edge to make 8 4x6 inch rectangles
with the long side facing you cut 3-4 slashes on the right side of the dough rectangles as in the picture, this will be the side you fold over the sausage[mv_schema_meta name="cut 3-4 slashes on the right side of the dough rectangles"]
line a baking sheet with parchment paper put one rectangle on the baking sheet
[mv_schema_meta name="lay one cylinder on the puff pastry dough on the side without slashes"]
fold the slashed side up and over the sausage, use a little water to seal it, and crimp with a fork
repeat with the remaining rectangles
mix the milk and agave together and brush over the sausage rolls as a glaze
bake for 20-30 minutes or until the pastry is puffed, browned, and crispy all over