Drain out the water from the tofu. Put the tofu and lemon juice into a food processor and blend until smooth. Set aside.
Mix the mascarpone cheese, icing sugar, and vanilla extract in a big bowl using a spatula. Fold in the tofu mixture until incorporated.
Heat whipping cream in double boiler over medium heat, until cream is warm to the touch, but not hot. Add gelatin powder and stir until it has dissolved. Remove from the heat. Fold in whipping cream mixture into the mascarpone cheese mixture until incorporated. Divide cheesecake mixture among cupcake cups, filling each cup 2/3 full. Cover with plastic wrap and place in the refrigerator.