These jumbo-size cookies, a New York City–bakery staple, are soft and cakey and would be quite plain save for the hint of lemon in the cookie and the assertive vanilla and chocolate icing on top. Although we provide a recipe, feel free to use your own favorite chocolate and vanilla icings. The only trouble with this cookie is figuring out which side to eat first!
- Preheat the oven to 400°F. Lightly grease your baking sheets, or line them with parchment; the cookies will fill four baking sheets, so you may need to bake in batches.
- To make the cookies: In a large bowl, beat together the butter, shortening, zest, salt, and vanilla. Beat in the sugar, then the eggs, one at a time, beating well after each addition.
- Whisk together the flour, baking soda, and baking powder. Add the flour mixture to the wet ingredients alternately with the sour cream, beginning and ending with the flour and adding the sour cream in three additions.
- Using a muffin scoop, a ¼-cup measure, or an ice cream scoop, drop the dough onto the prepared baking sheets in nice round balls. Flatten each ball to a circle ¼̋ to 3/8̋ thick, about 4½̋ across. Leave 2̋ to 2½̋ between each cookie.
- Bake for 10 to 11 minutes, until there’s a hint of brown at the edges. Cool for 5 minutes on a rack. Cover the pans with a clean dish towel while the cookies finish cooling to keep them soft. When they’re completely cool, seal the cookies in a plastic bag so they stay soft. Let them rest for at least an hour before icing them.
- To make the icing: Melt the butter in a large saucepan over low heat. Remove from the heat, then stir in the yogurt, and 4 cups of the confectioners’ sugar. The icing will be soft and runny. Immediately separate it into two halves, 1 cup each. Add the remaining ¼ cup confectioners’ sugar to half of the white icing, and the chopped unsweetened chocolate to the other half. Stir to melt the chocolate. Set the chocolate icing in a pan of hot water, or in a saucepan over very low heat, to keep it spreadable.
- Dip one side of the top of each cookie into the white frosting and put it on a rack to drip and dry. As soon as you can handle the cookies without leaving fingerprints in the frosting, dip the other side of each cookie in the chocolate frosting.