Setting on pan: Remove the oregano sticks to leave just the leaves.Spread the parsley, thyme, cilantro, oregano, garlic, and onion on a baking sheet.
Drying in dehydrator: Place in dehydrator for 4-5 hours, or until completely dry (they will crumble when pressed). Drying in oven: Dry on metal tray in the oven at 176 ºC [80 ºC] (or as low as possible) for 4 hours, or until all ingredients are dry (they will crumble when pressed).Drying in microwave: Microwave herbs only (no garlic or onion - see notes) on a microwave-safe tray for 30 seconds. Check to see that they are completely dry (they will crumble when pressed). Microwave for another 10 seconds if they need to be dried some more.The color of the resulting powder will depend on the combination of herbs and the drying method.
Cleaning: Remove from the oven/dehydrator/microwave and remove the remaining oregano and thyme sticks, leaving only the leaves.
Pulverizing: Pulverize in a food processor or coffee grinder.
Storing: To store, put in an airtight container in a cool, dry place (see notes).Use it to season vegetables, meats, and fish.
Video
Notes
Garlic and onion take too long to dry in the microwave, regardless of how thin it's minced/sliced, and it eventually burns a bit, so it doesn't work. In that case, make a herb-only seasoning, or add store-bought dry garlic and onion. This is my preferred method, actually, because it's speedy, energy-efficient, and uncomplicated.Do you have any other herbs at hand (leek, chives, culantro, etc.)? Throw them in too!I do not recommend adding salt to it. Salt is hydrophilic (will attract water from the air) and make it damp and last much less time. If you make a batch that is going to last more than a week, it's best to refrigerate it, out of an abundance of caution.