MAKE DOUGH: Melt unsweetened chocolate over double boiler, or in the microwave, in 30-second intervals. Set aside to cool slightly. Stir together flour, cinnamon & salt with a whisk until fully incorporated. Cream butter and both sugars until light and fluffy. Add coffee mixture, melted unsweetened chocolate and egg to butter/sugar mixture, beating well and scraping down sides with a rubber spatula as needed. Add flour mixture gradually and mix until just combined. Cover and chill dough in bowl for 1 hour until it’s easy to handle.
SHAPE DOUGH INTO LOGS & CHILL: Shape dough into two 7-inch rolls. Wrap in parchment or wax paper and refrigerate for at least 6 hours or overnight.
SLICE & BAKE COOKIES: Preheat oven to 350 degrees F. Remove rolls of dough from refrigerator and slice with a serrated knife as evenly as possible, to a generous ¼ inch thickness. Place cookies onto ungreased baking sheet and bake for 10-12 minutes. Cool on a cooling rack until ready to dip.
DIP COOKIES: Meanwhile, in a heavy saucepan over low heat, or in the microwave in 30-second intervals, melt chocolate chips with coconut oil, and stir until smooth and shiny. Pour into a wide microwave-safe cup or bowl. Dip half of each cooled cookie into the chocolate mixture, and place on a sheet of wax paper until chocolate is set.