Preheat your oven to 400F (200C). Line with parchment paper or grease a 9"x 12" baking dish.

Make the dough: In a large bowl, whisk together the flour, baking powder, and salt. Add in the vegan butter cubes and use a pastry cutter or fork to cut the butter into the flour until you reach a grainy texture. Pour in the plant-based milk and combine to make a shaggy dough.

Either in the bowl or on a clean work surface use your hands to knead the dough together incorporating any leftover dry ingredients until it all comes together into a nice ball. Let the dough rest in the bowl for 10 - 15 minutes before proceeding.

Once the dough has rested, lightly flour a clean work surface and roll the dough with a rolling pin until you get a rectangle about 19" x 14".

Pour the melted vegan butter over the rolled out dough and use a pastry brush or the back of a spoon to spread evenly over the dough. In a small bowl mix together the brown sugar and cinnamon, then sprinkle the cinnamon sugar evenly over the melted butter.

Starting from a longer side of the dough rectangle, use your hands to gently roll the dough up. Once rolled, use a sharp knife to cut 12 cinnamon rolls by gently sawing with the knife.

Place the cinnamon rolls in the baking dish, swirl side up, and bake for 24 - 28 minutes until puffed up and lightly golden. Let cool for 10 minutes before serving.

Optional icing: Combine the powdered sugar, vegan butter, vanilla extract, and lemon juice or plant-based milk together in a small bowl. Spread the icing roughly over the still warm cinnamon rolls.