Preheat the oven to 350°F. In a medium bowl, whisk together the dry ingredients- flour, baking soda and salt. In a separate bowl, use and electric mixer to combine the butter and sugars until light and fluffy. Add in the sour cream, egg and vanilla; beat until smooth. With mixer on low, gradually add the flour mixture; mix in the chocolate chips.
BAKE THE COOKIES:
Using 1 rounded tablespoonful per cookie, drop mounds of dough about 1 1/2 inches apart onto two baking sheets. You should be able to make 24 to 28 cookies. Bake until golden, 10 to 12 minutes; transfer to a rack to cool completely, then transfer to a freezer to chill. Place a baking sheet in the freezer to chill as well (you'll be using it to place the ice cream sandwiches on).
ASSEMBLE THE SANDWICHES:
Scatter the remaining chocolate chips on a plate. Place about 2 tablespoons of ice cream between 2 chilled cookies (bottoms facing in); press gently. Roll the sides of each sandwich in chocolate chips and place immediately on the chilled baking sheet in the coldest part of your freezer. Repeat with the remaining cookies/ice cream/chips. Let the sandwiches chill well in the freezer (45 to 60 minutes); then wrap individually in plastic wrap. Store in the freezer until ready to serve!
Notes
*Store wrapped sandwiches in the freezer for up to 2 weeks.