1 1/3 cups all-purpose flour
1/2 cup unsweetened cocoa powder
1 teaspoon baking powder
1/2 teaspoon baking soda
1/4 teaspoon Kosher salt
1/4 teaspoon ground cinnamon
1 1/2 teasoons coffee powder (use espresso powder if you are a coffee fan)
1/2 cup hot water
1 teaspoon vanilla extract
1/2 cup whole milk, plain yogurt, or sour cream
1/4 pound (1 stick) unsalted butter, at room temperature
1 cup sugar
1 egg
1. Preheat the oven to 375 degrees. Line 18 muffin cups with paper baking cups.
2. Place the flour, cocoa powder, baking powder, baking soda, salt, and cinnamon in a bowl and mix to combine.
3. Place the coffee powder and water in a small bowl and mix until the coffee has dissolved. Add the vanilla and milk and mix until well combined.
4. Place the butter and sugar in the bowl of a mixer fitted with a paddle and beat until light, fluffy, and light lemon colored, about 3 to 5 minutes. Add the egg and beat well. Scrape down the sides of the bowl, and half of the flour mixture, and beat well. Add the coffee mixture and then the remaining flour mixture.
5. Scrape down the sides of the bowl and fill the prepared muffin tins two-thirds full. Transfer to the oven and bake until a toothpick inserted in the center comes out clean, about 20 minutes. Set aside to cool.