Line a 9x13" with parchment paper.
Combine brown sugar, butter, honey, cocoa powder and vanilla in a saucepan over medium. Bring to gentle boil and allow to boil for 1 minute. The syrup mixture should be smooth, under or over boiling can result in a grainy syrup.
Pour the syrup over puffed wheat and mix until all puffed wheat pieces are coated.
Press into prepared pan and allow to cool.
Store in an air tight container.