In a large bowl, combine oats, nuts, and brown sugar.
In a separate bowl, combine oil, maple syrup, vanilla, and salt. Pour over oat mixture and toss to coat. Spread mixture out onto two baking sheets and bake 1 hour to 1 hour 15 minutes, stirring every 15 minutes.
Remove from oven and scrape mixture into large bowl. Let cool for a few minutes then sprinkle matcha over and toss to combine.