Combine the sugar and water in a small saucepan. Bring to a boil over moderate heat, stirring to dissolve the sugar. Stir in the brandy and vanilla extract. Remove from the heat, transfer to a shallow bowl, and let cool.
In a large bowl, stir the ricotta with the 1 cup of the peppermint candy, 4 tablespoons of grated chocolate and 1/2 cup of the cooled brandy syrup.
Pour espresso into remaining brandy syrup.
Choose a dish that measures about 7 by 10 inches. One at a time, dunk half the ladyfingers in the brandy syrup to moisten them well, and then arrange them in a single layer in the bottom of the dish. Spread half the ricotta mixture evenly over the ladyfingers (you can also use a pastry bag). Moisten the remaining ladyfingers with the remaining syrup and arrange them over the ricotta. Top with the rest of the ricotta, spreading it evenly. Sprinkle the top with the remaining 2 tablespoons grated chocolate and the remaining peppermint candy. Cover and refrigerate for several hours before serving.