Preheat your oven to 325°F (160°C). Grab a baking sheet and line it with parchment paper for easy cleanup.
In a food processor, pulse the pecans, walnuts, almonds, and hazelnuts a few times until they are roughly chopped but still have some larger pieces for that satisfying crunch.
Now, add the pumpkin seeds, chia seeds, almond flour, ground flaxseed, sugar-free sweetener, cinnamon, and nutmeg to the food processor. Pulse a few more times until everything is just combined. Remember, we want some texture, so don't over-process it!
Pour this dry nut and seed mixture into a large mixing bowl.
In the same food processor (no need to wash it!), whisk the egg white until it's light and frothy.
Add the melted coconut oil, sugar-free maple syrup, and vanilla extract to the frothy egg white, and give it a quick mix until well combined.
Pour these wet ingredients over your dry nut and seed mixture in the large bowl. Stir everything together really well until all the dry bits are evenly coated.
Spread the granola mixture thinly and evenly onto your prepared baking sheet. This helps it bake consistently and get super crispy.
Bake for 10 minutes. Then, gently remove the tray from the oven and give the granola a stir.
Return it to the oven and bake for another 10 minutes. Remove it again, stir in the unsweetened flaked coconut, and bake for a final 10 minutes, or until the coconut is lightly golden and the granola looks wonderfully crisp. Keep a close eye on it during this last step, as coconut can brown quickly!
Once baked, remove the granola from the oven and let it cool completely on the baking sheet at room temperature. It will get much crunchier as it cools down.
Once fully cooled, break it into delicious clusters and store your homemade keto granola in an airtight container. Enjoy it as a cereal with unsweetened almond milk, sprinkled over yogurt, or simply as a healthy, crunchy snack!