Preheat the oven to 325°F (165°C) and line a large rimmed baking sheet with parchment paper.
In a large mixing bowl, combine the oats, pecans, flaxseed, cinnamon, ginger, and salt.
In a separate medium bowl, whisk together the mashed banana, maple syrup, melted coconut oil, and vanilla extract until smooth.
Pour the wet ingredients over the dry oat mixture and stir until thoroughly and evenly coated.
Spread the mixture onto the prepared baking sheet in an even layer, pressing down firmly with a spatula to encourage clusters.
Bake for 35 to 40 minutes, stirring once halfway through, until the granola is fragrant and deep golden brown.
Remove from the oven and let cool completely on the baking sheet for at least 30 minutes to allow the granola to crisp and form clusters.