Using a clean coffee grinder or high-speed blender, grind the oatmeal and lavender into a fine powder. Set aside.
In a clean bowl, combine the oatmeal powder, lavender powder, and rice flour. Mix thoroughly.
Melt the tallow.
Add the essential oil to the melted tallow and mix well until fully incorporated. Then add to the powders.
Transfer to a clean, airtight container.