Place the ricotta in a food processor and blend until very smooth. Pour in the caramel sauce and milk and process again until completely blended. Add the chocolate chips and pulse 2 to 3 times just to combine.
Pour the mixture into a resealable gallon-size plastic freezer bag, using a rubber spatula to get all the ricotta mixture into the bag. Press out the excess air and seal, and then place inside a second plastic bag and seal. Press on the ricotta mixture to distribute evenly inside the bag. Freeze for at least 3 hours or up to 2 weeks.
Before serving, transfer the bag to the refrigerator until slightly softened, 15 to 20 minutes.
For easy serving, remove the outer bag and then reinforce one of the bottom corners of the ice cream bag with several layers of masking tape. Snip through the center of the tape to make a hole or spout. Push the ice cream out of the bag and into dessert cups by squeezing and twisting from the top.
Cook's Note: For an alternative freezing method, pour the ricotta mixture into a 9-by-9-inch baking dish. Cover loosely with plastic wrap and freeze, stirring well with a wooden spoon every 15 minutes, until desired firmness is reached.