Preheat the oven to 150 C and line a baking sheet with a silicone mat or wax paper.
In a large mixing bowl, whisk together the olive oil, honey, peanut butter and vanilla.
Add the oats, almonds, cocoa powder and salt. Fold very well with a silicone spatula or wooden spoon, making sure every inch of the mixture is coated.
Tip the mixture onto the baking tray and spread it out in an even layer, but pressed together firmly.
Bake for 15 to 20 minutes when the edges will have darkened, then gently stir and flip the granola to ensure even cooking. Clusters may have started to form already, so just move them around without breaking them up. Drizzle the granola with an extra tablespoon of honey to encourage more 'clumping' and then continue baking for another 15 minutes until evenly browned and fragrant.
Allow the baked granola to cool. As it cools, it will firm up more. Once completely cooled, break into smaller clumps or clusters. I store the clusters in one box and the remaining loose granola in another, to eat as cereal or with yoghurt.
Store in an airtight jar at room temperature for about a week (in humid weather, longer in dry weather), or refrigerate for a month and freeze for even longer. Eat the clusters by the handful!