Preheat oven to 400F and line a baking sheet with parchment paper.
Lay puff pastry out and cut it into 12 squares/rectangles, or use fall cookie cutters like I did, if you're feeling fancy. Arrange them on the baking sheet, at least 1-inch apart.
With a knife, lightly score a line, 1/4-inch away from the sides, along each side. This will help the pastry to rise around the filling.
In a mixing bowl, stir pumpkin puree, soymilk, brown sugar, cinnamon, vanilla, lemon juice, and salt, until combined. Taste and adjust spices to your liking, if necessary.
Place a few spoonfuls of filling onto each piece of puff pastry, within the frame you scored. In a small mixing bowl, stir pecans, maple syrup, vanilla and salt together. Top each pastry with sweetened pecans.
Place pastries in oven, and bake for 20 minutes, or until the puff pastry has risen and is golden brown. While those are baking, in a small bowl, whisk powdered sugar, maple syrup and soymilk together, until smooth. Set aside.
Once pastries are baked, wait at least 10 minutes for them to cool; then drizzle with glaze. Wait longer if you want to serve them at room temperature. Enjoy!