1Start with your buttermilk powder, then add your herbs and spices.
2Whisk until the color looks totally even and speckled all the way through.
3If your herbs are huge and you want a tighter texture, you can pulse this once or twice in a spice grinder. If you don't have a spice grinder, an immersion blender is going to work perfectly for this.
4Be very careful. Do not fully powder it or it will clump faster.
5Funnel this into an airtight jar, and give that a nice shake and label it.