Triple Chocolate Cinnamon Cookies

Position rack in center of oven and preheat to 350 degrees F. Line cookie sheets with parchment paper or a silicone pad. Place flour, cocoa powder (chocolate #1), cinnamon, baking powder and salt in a bowl and stir with a wire whisk to combine. In another bowl (or the bowl of a stand mixer) beat the butter, sugar, and eggs until smooth. Stir in the melted semisweet chocolate(chocolate #2) until smooth. Mix in the dry ingredients just until combined. By hand, stir in the milk chocolate chips (chocolate #3) and the chopped walnuts.
Drop dough by tablespoonfuls onto prepared cookie sheets, spacing 2 inches apart, as the cookies will spread. Press a walnut half into each cookie. Bake until cookies look dry and cracked, about 11 minutes, but checking after 8 minutes. Let cookies stand on sheet for 5 minutes then transfer to a rack and cool completely.
If desired, dip fork tines into melted semisweet chocolate. Wave fork over cookies, drizzling melted chocolate using your best Jackson Pollock style. Let stand until chocolate sets.
These cookies can be prepared ahead. Wrap airtight and let stand at room temperature 2 days or freeze 1 month. Alternatively freeze the prepared dough by rolling into a log in a large sheet of parchment paper. Keep the dough log in the parchment and then tightly wrap again in plastic wrap. Keep in freezer up to 6 months, slicing and baking from the frozen log as needed. Increase cooking time accordingly.