Preheat oven to 300F. Line a baking sheet with parchment paper or Silpat. Mix nuts and seeds in a bowl. Toss thoroughly with cinnamon, chili powder, cayenne pepper, and salt. In a small saucepan over medium low heat, warm the coconut oil and honey. Pour liquid mixture over the dry mixture. Mix well. Spread the mixture evenly onto the prepared baking sheet and bake for 20-25 minutes, until golden brown, tossing at the halfway point. Allow for it to cool COMPLETELY, at least 30 minutes, or until hardened (and sticky). Break apart and store in an airtight container.
In the meanwhile, pour milk and water into a pot and bring to a boil. Pour in the steel-cut oats and stir. Bring pot back to a boil (Do not walk away as liquid may overflow out of the pot). Reduce heat to low to allow for oats to simmer for 20-30 minutes depending on your desired consistency. It's important to stir occasionally. Cook longer for thicker pudding. Serve immediately with the nut clusters (Optional: Add some orange zest for a bright citrus kick). Leftovers can be stored in an airtight container in the fridge. When reheating, stir in a bit of milk to loosen up the oats.