Place chocolate chips in a large bowl and melt over a double boiler or in the microwave. Once melted, add the vanilla extract. Set aside.
In medium bowl, mix together the brown rice cereal and the tahini. Add this mixture to the chocolate and mix well.
Take out a mini muffin pan and line with mini baking cup liners. Fill each muffin liner cup with the crispy tahini chocolate mixture, then place in refrigerator to quickly firm up (about 5 minutes). Remove the cups from the pan and place in a covered container. Repeat process with remaining mixture.
Store chocolate cups in a cool, dark place or in the refrigerator for up to 3 weeks.