Sorbet gives these ice cream cookie sandwiches a tart twist. Martha made this recipe on Martha Bakes episode 607.
Preheat oven to 350 degrees, with racks in upper and lower thirds. Whisk together flour, baking powder, and salt.
In a bowl of an electric mixer fitted with the paddle attachment, beat butter and sugar on medium-high until pale and fluffy, about 3 minutes; scrape down bowl as needed. Beat in eggs, one at a time. Add both vanillas and beat to combine. Add flour mixture and mix to combine.
Using a 1 1/2-inch ice cream scoop, drop dough onto parchment-lined baking sheets, spacing 2 inches apart. Bake until edges are lightly golden, 12 to 14 minutes. Transfer cookies to a wire rack to cool. Allow baking sheets to cool and repeat process with remaining dough.
Scoop 1/4 cup sorbet onto the flat sides of half the cookies; sandwich together with remaining cookies. Serve immediately, or wrap in waxed paper and freeze on a baking sheet until firm, up to 1 day.