Line a sheet pan or tray with parchment paper and set aside.
Melt the butter in a medium saucepan over medium heat.
Add the oats and cook, stirring frequently, until they become golden, aromatic, and about one shade darker. About 3 minutes
Reduce the heat to low and stir in the turbinado sugar, cocoa powder, peanut butter, water, and sea salt until well combined.
Increase the heat just enough to bring the mixture to a gentle boil, then reduce to a simmer. Cook for 5 to 10 minutes, stirring occasionally, until the liquid is absorbed and no visible liquid remains in the pan.
Remove the saucepan from the heat and stir in the vanilla extract.
Using a small cookie scoop or two spoons, portion the mixture into 1 ounce bites and place them on the prepared parchment lined tray. Once cooked to the touch lightly grease hands and smooth the bites. (Tossing with cocoa powder optional)
Allow the bites to cool until firm, then refrigerate until chilled before serving.