In a small bowl, combine cold water and gelatin; let stand for 2 minutes. Add boiling water; stir until gelatin is dissolved. Cool slightly. In a mixing bowl, combine sugar and cocoa. Add the cream and vanilla; beat on medium speed until stiff peaks form. Add gelatin mixture; beat just until blended. Spoon into dessert dishes. Chill for at least 30 minutes. Garnish with toffee bits. Store leftovers in the refrigerator.