Preheat oven to 325°. Spray a 6-mold miniature fluted tube pan* with baking spray with flour.

In a small bowl, whisk together cocoa, ¼ cup boiling water, and espresso powder until smooth. Let stand until cooled to room temperature.

In a large bowl, beat butter, sugars, and vanilla with a mixer at medium speed until fluffy, 3 to 4 minutes, stopping to scrape sides of bowl. Add eggs, one at a time, beating well after each addition.

In a medium bowl, whisk together flour, baking powder, and salt. With mixer on low speed, gradually add flour mixture and cocoa mixture to butter mixture, beating until combined. Beat in melted chocolate. (Batter will be thick.) Spoon batter into prepared molds, smoothing tops. Tap pan on counter twice.

Bake until a wooden pick inserted near center comes out clean, about 25 minutes. Let cool in pan for 10 minutes. Remove from pan, and let cool on a wire rack for 30 minutes. Spoon Bittersweet Chocolate Glaze over cakes. Serve with Brandied Whipped Cream. Garnish with cinnamon, if desired.