Preheat & Prepare: Preheat oven to 180°C (350°F). Line a 9x13 inch baking tin with greaseproof paper.
Mix Dry Ingredients: In a large bowl, whisk together flour, brown sugar, cinnamon, baking soda, and salt.
Mix Wet Ingredients: In a separate bowl, combine soy milk, oil, apple cider vinegar, vanilla extract, and instant coffee powder. Stir well.
Combine Batter: Gently fold wet and dry ingredients together until just combined. Do not overmix.
Layer the Batter: Pour half the batter into the prepared tin and spread evenly.
Add Cinnamon Swirl: Sprinkle the cinnamon-sugar mix evenly over the first layer of batter.
Add Remaining Batter: Pour the remaining cake batter on top and spread evenly.
Prepare Streusel: Mix brown sugar, cinnamon, and melted vegan butter. Sprinkle on top of the cake batter.
Bake: Bake for 35-40 minutes or until a skewer inserted into the center comes out clean.