Place the raspberries in a blender or food processor. Add the yogurt, sugar, fresh lemon juice and vanilla. Pulse until raspberries are smooth.
Pour purée through a fine mesh strainer into a bowl, pressing on solids with back of a spoon. Stir in chambord or vodka. Set aside.
Place semisweet chocolate in a medium heatproof bowl. Set bowl over saucepan containing barely simmering water; heat mixture until chocolate is melted and whisk until smooth. Stir in oil and transfer to a ziploc bag; set aside.
Pour the mixture into the ice cream canister and churn following the manufacturer’s instructions until the mixture resembles the consistency of thick whipped cream.
Snip the corner of the ziploc bag that the chocolate is in, and while the machine is running, slowly drizzle the chocolate into the frozen yogurt. After chocolate is added, continue churning until the mixture resembles soft served ice cream.
Transfer the frozen yogurt to an airtight container. Cover the container and freeze until it is firm, about 3 hours.