Click on the recipe book next to Broosha and scribe Makin Stuf Da Grobb Way which gets placed in your inventory. This only needs to be done the first time you do one of the Goodies for Grobb quests, as you will get all of the recipes needed.
Collect the material you will need in Grobb, specifically:
5 mud-caked lumber, which can be collected from fallen lumber found underneath trees in the swamp near Grobb.
15 congealed goo, which can be collected from slimy slugs found in a conduit around ( -444, -72, -964 ) Copy/waypoint -444, -72, -964.
10 malodorous clay, which can be collected from clay deposits in the central river of Grobb.
