Preheat oven to 350º F. Line a large baking sheet with parchment paper.
Combine the oats, nuts, salt, and cinnamon in a large mixing bowl; stir until thoroughly mixed.
Add the oil, maple syrup or honey, and vanilla. Stir again, until everything is evenly coated. Carefully dump the granola onto the parchment-covered pan. With a large wooden or silicone spoon, spread the mixture into an even layer.
Place baking sheet in the oven and bake until the oat mixture is lightly golden, about 20 to 25 minutes; stir halfway through.TIP: In order to get some good clumps and clusters, press the stirred granola down with your spatula to create a more even layer before returning it to the oven. Note that the granola will crisp up even more as it cools.
When done, remove the granola and let it cool. (Leave it undisturbed for at least 45 minutes.)
Once cool, top with raisins. Break the granola into pieces with your hands if you want those nice big clumps and clusters. If you don't want a cluster-y granola, simply stir it around with a spoon and break it apart as much as you can.