In a small saucepan, bring the sugar, water and cardamom to a simmer over medium heat.
Simmer for 5 minutes, remove from the heat and let cool for 20 minutes.
Strain, and stir in the pear brandy.
(This mixture can be made up to 2 days ahead of time.) Add half an ounce of the pear-cardamom mixture to each of 6 white wine or coupe glasses.
Top each glass with 4 ounces of Champagne.
To garnish, core 2 Forelle or Seckel pears and cut into eighth-inch slices.
Garnish each glass with 3 pear slices spread into a fan shape.