In a small bowl combine the yeast, warm water and brown sugar. Give it a gentle stir and allow it to sit until the mixture becomes frothy.
In the meanwhile, in a large bowl, combine the flour, salt, baking powder, and baking soda. Stir to combine.
Next, add the vegan sour cream and oil to the yeast mixture. Stir to combine. Pour this sour cream mixture into the flour and stir. The mixture will be sticky. Once the dough has come together, cover with a kitchen towel and place in a warm place in the kitchen. Set aside to rise for about 45 minutes.
Once the dough has doubled in size, get out a small bowl and place some extra flour in it. Also get out a pan sprayed with vegetable spray. Now punch down the dough and make 8 -10 balls that are approximately the size of a golf ball. Use the flour to help shape the balls because the dough will be sticky (which is what you want). Set these aside to rise another 30 minutes.
When you're ready to bake your Naan, turn your oven to 350I used a pizza pan and gave it a light coating of vegetable spray. Use the flour to help you flatten the dough balls into small, flat pieces, about 6" in diameter. Spray the top side with a light layer of vegetable cooking spray or olive oil. Place on the prepared pan. When you have them all arranged on the pan, carefully place them in the hot oven. Allow them to cook for 4-5 minutes on one side. Use a tong to pull up one of them to see if it's adequately brown on the bottom side. If so, remove from the oven and flip the Naan and cook on the other side for 4-5 minutes as well.