Disclaimer: I do not own Harry Potter or anything about it except my fan fictions, and these ingredients and their mixture are all but made up, they're not canon.
Ignatia Wildsmith's Formula For Floo Powder
HIGHLY CLASSIFIED!
1. Floo Plant – three leaves per scoop. The heart of the Floo powder.
2. Moonstone – one gem per scoop. Makes the powder and conjured fire shine pale green.
3. Ashwinder eggs – half of one per scoop. Ignites the flames which consume the traveler and take him/her to another fire.
4. Daisy – two and one third daisies per scoop. Muffles the inevitable discomfort which comes through the Floo Network.
5. Cinnamon – three tablespoons per scoop. Soothes the people's skin and nerves while passing through the flames.
6. Nightshade – four drops per scoop. Protects the Floo Network from undesirable users magically.
7. Salamander blood – two teaspoons per scoop. Fuels the Floo Network and keeps it running without getting extinguished permanently.
NEVER REVEAL THE SECRETS OF THIS MIXTURE TO ANYONE, NOT FOR ANY REASON WHATEVER! ITS SECRET MUST BE KEPT SECRET AT ALL COSTS, SO AS DARK WIZARDS AND WITCHES MAY NOT MANIPULATE IT FOR THEIR OWN PURPOSES. AND ALWAYS MIX THESE INGREDIENTS IN THE ORDER I HAVE LISTED THEM! MAY IT SERVE THE WIZARDING WORLD WELL AFTER I HAVE PASSED ON.
Yours etc.,
Ignatia Wildsmith