In a medium bowl, whisk the flour with the baking soda and salt until well blended.
With a stand mixer (use the paddle attachment) or a hand mixer, beat the butter and ricotta on medium-high speed until light and fluffy, about 2 minutes. Add the sugar, orange zest, and vanilla; beat until blended, about 3 minutes. Scrape the bowl. On medium speed, add the egg and beat until blended. Add the flour mixture and mix on low speed until almost completely blended. Pour in the chocolate chips and continue mixing until just incorporated. Scrape the dough down from the sides of the bowl, cover with plastic, and refrigerate until slightly firmer, about half an hour.
Heat the oven to 350°F. Line large baking sheets with nonstick baking liners or parchment. Drop the batter by rounded tablespoons about 2 inches apart on the prepared baking sheets. Bake until the cookies are light golden, about 15 minutes. Let the cookies cool on the sheets on racks for 5 minutes before transferring them to racks to cool completely.
Store at room temperature or freeze in an airtight container, separating the cookie layers with waxed paper.
Photo: Scott Phillips