Heat up some oil in a non-stick frying pan and sauté chopped onions, celery and garlic until nice and soft but not too coloured. Set aside to cool slightly.
Peel the skin off the sausages and put them in a large bowl.
Preheat the oven to 190C(fan)/375F/Gas Mark 5.
To the bowl with sausages add pureed beans, sage and onion stuffing mixture and sautéed veggies.
Season with salt and pepper and give it all a good mix until well combined.
To assemble, roll out your puff pastry sheet and cut it in half lengthwise.
Divide sausage filling mixture into two and place it in the middle of each rectangle forming two long sausage like shapes.
Roll one side of each pastry rectangle over the filling following up with other side making sure that it is overlapping nicely and completely encasing the filling.
Place both long sausage rolls seam side down and cut into 12 mini sausage rolls each.
Place them onto prepared baking sheet (lined with baking paper if not quite non-stick), score them gently with a knife if you want to and brush over some plant based milk. Feel free to sprinkle some sesame or poppy seeds.
Bake in preheated oven for 25 minutes until your sausage rolls are nice and brown. If your oven is anything like mine you will want to turn baking tray around half way through to ensure even baking.
Once done, let them cool slightly and enjoy!