Combine water and honey in a small saucepan. Bring to a boil, then reduce heat to medium low. You want the mixture to continue boiling, but not spill out of your pan.
Boil until you mixture reads 245°F on a candy thermometer.
Add nuts to mixture and stir. Cook for about 10 more minutes, until your mixture is a rich golden brown in color. Constantly whisk to prevent scorching.
Remove pan from heat and stir in baking soda, butter, and vanilla extract. Whisk until well combined.
Pour on a silicone baking mat or parchment paper and allow to cool. Spread, only if needed - you want the brittle to be about 1/4" thick (not counting the nuts).
When the candy is completely cool, break into smaller, easy-to-handle pieces. (TIP: For easier breaking, you can also place in the freezer for 5 minutes after the candy has already reached room temperature.)
Notes
Note: Nutrition information is a rough estimate only; actual values will vary based on the exact ingredients used and amount of recipe prepared.