
Prepare a loaf pan ( 9 by 5 inch) by lining with parchment or greasing. Preheat the oven to 350 degrees F ( 180 deg C).
Mix the non dairy milk and vinegar and let sit for 2 mins. Then add the rest of the wet ingredients and whisk well to combine. Sugar should be well combined.
Add 1 3/4 cup flour*, starch, baking powder, baking soda and salt (through a sieve or mixed in another bowl). Whisk well to combine. Add in the rest of the flour 1 tbsp at a time, if needed. The mixture should be a flowy but just slighty stiff (depends on the flours used). You can also in some spices into the flour for other flavors.(*If using whole grain flour, start with 1 3/4 cup flour. You might not need more).
In a small bowl mix the cinnamon, sugar and a good pinch of salt. Press down with a spoon and mix until the cinnamon is mixed in.
Add half of the batter to a prepared loaf pan. Sprinkle half of the cinnamon mixture on the batter. Pour the rest of the batter and even it out. Sprinkle the remaining cinnamon mixture on top. Use a knife to swirl in lightly throughout the batter. Spray oil on top to seal in the cinnamon mixture
Bake for 50 to 60 minutes (depends on the pan and oven) Check from the center at 45 mins and continue baking till the toothpick comes out completely clean.
Cool on the counter for 10 mins then remove from the pan and continue to cool completely before slicing. Slice and Store on the counter for upto 2 days and refrigerated for upto a week. Slices can also be frozen. Add an icing for dessert.