Heat your oven to 300ºF and lightly grease a large sheet pan with non-stick cooking spray.
In a large bowl, combine the oats, nuts, hemp hearts, wheat bran, flour, brown sugar, salt, and cinnamon.
In a 2-cup glass measuring cup, whisk together the maple syrup, oil, hot water, and vanilla. Pour the wet ingredients over the dry and stir very well to combine and evenly coat.
Transfer the granola to the prepared sheet pan and bake for 50 minutes to 1 hour or until golden and crisp to the touch.
Turn the oven off and set a timer for 15 minutes, leaving the granola in the oven. This will allow the granola to further crisp up and help keep the granola chunky.
Remove the granola from the oven and allow it to cool completely on the sheet pan. When cool, gently break the granola up and transfer to an airtight container. The granola will keep at room temperature for up to 1 month.
