Peel pears; halve through stem end and core pears; sprinkle with lemon juice to prevent discoloring.
In 12-inch skillet, combine water and sugar. Bring to boiling, stirring to dissolve sugar. Reduce heat to medium; simmer 5 minutes. Add vanilla extract and pears, cut side down. Spoon some syrup over pears. Cook, covered, 10 minutes. Turn pears over, cut side up. Cook, covered, 10 minutes more or until pears are translucent and knife-tender. Remove from heat; let pears cool in liquid.
In medium-size heavy-bottom saucepan, combine chocolate, coffee and sugar; cook over low heat, stirring occasionally, until chocolate is melted. Add cream; gently cook until heated through, about 2 minutes.
To serve, arrange pears, cut-side down, on serving plates. Pour some chocolate sauce over each. Serve with vanilla ice cream and garnish with candied violets, if desired.