In a saucepan, combine the ground ginger and mineral water. Bring to a boil, then reduce the heat and simmer for 10 minutes.
Remove from the heat and strain the ginger mixture through a fine sieve or cheesecloth into a large bowl.
Add the sugar (or honey) to the ginger liquid and stir until dissolved.
Allow the mixture to cool to room temperature.
Once cooled, add the sparkling water and a few drops of lemon juice.
Transfer the ginger beer to a clean, airtight container and refrigerate for at least 4 hours, or until cold.
Serve over ice and garnish with lemon slices. Enjoy your natural, delicious, healing ginger beer!
