Snickerdoodle Thumbprint Cookies with Chocolate

To prepare chocolate filling: Put chocolate in a small, deep heatproof bowl. Set a fine sieve by the bowl. Put milk in a 2-cup microwave-safe glass measuring cup and microwave on High just until it begins to boil and foam up the sides, 40 to 60 seconds. Pour half the hot milk through the sieve onto the chocolate and let stand without stirring for about 2 minutes to soften the chocolate. Stir vigorously until smooth and the chocolate is mostly melted.

Pour the remaining milk through the sieve into the bowl. Add vanilla. Stir vigorously until smooth. Sift confectioners' sugar onto the mixture and stir in thoroughly. Refrigerate until very cold and stiff.

To prepare cookies: Position a rack in middle of oven; preheat to 350 degrees F. Line a large baking sheet(s) with parchment paper.

Whisk all-purpose flour, whole-wheat flour, baking powder and salt in a medium bowl. Beat oil, butter, 1/2 cup plus 1 tablespoon sugar, egg and lemon zest in a mixing bowl with an electric mixer on low speed until well blended. Beat in honey, vanilla and almond (or lemon) extract until evenly incorporated.

With the mixer on low speed, then medium speed, beat about half the flour mixture into the wet ingredients until incorporated. Beat in the remaining flour mixture until just incorporated.

Divide the dough into quarters. Roll each quarter into a 9-inch "log." Slice the log into 12 equal pieces. Roll each piece into a ball.

Combine the remaining 4 tablespoons sugar with cinnamon in a small bowl and transfer to a plate. Roll each ball in the cinnamon-sugar. Place about 1 1/2 inches apart on a prepared baking sheet. Press a well into the center of each cookie with a thumb. Fill with about 1/2 teaspoon of the cold chocolate filling.

Bake the cookies on the center rack, one pan at a time, until firm when pressed near the edge, 8 to 12 minutes. Let stand for 5 minutes, then transfer to wire racks to cool to room temperature.