In a small saucepan add the sugar and the water and bring to a boil over medium-high heat. Stir continuously until the mixture becomes syrupy. Usually at this point it will produce a lot more bubbles. About 2-3 minutes.
Reduce heat to medium and add in the fennel seeds. Continue to stir until the mixture crystalizes. This will happen from one second to the next and the fennel seeds will look almost dry. Quickly remove from heat and continue to stir a few more seconds until the fennel seeds are dry and separated. Pour into a sealable air-tight container.
Sprinkle on salads, desserts, oatmeal, etc. Or use to freshen breath after a spicy meal :)