Chocolate Sour Cream Cupcakes with Chocolate Espresso Buttercream

1. Preheat oven to 350°F.
 Line 2 muffin tins with 16 liners, 8 in each, filling remaining slots halfway with warm water. 

2. In a large mixing bowl, whisk together flour, ½ cup cocoa, baking powder, baking soda and salt. Set aside. 

3. In a stand mixer fitted with a
 paddle attachment or in a large bowl using a handheld electric mixer, beat eggs, cane juice and oil on medium high until pale yellow in color and doubled in volume, 2 to 3 minutes. Reduce speed to low and add sour cream, ½ cup milk and vanilla and
 beat until combined. Stop machine
 and add flour mixture. Mix on low until combined, then beat
 on medium-high for 2 minutes. Divide batter among liners, filling
 each two-thirds full. Bake until a
 toothpick inserted in the center
 comes out with fudgy crumbs, 10 to 12 minutes, being mindful not to over bake. Transfer cupcakes to
 a wire rack to cool completely. 

4. Meanwhile, in a food processor, process dates and butter until
 smooth, 4 to 5 minutes. Add remaining ¼ cup cocoa and espresso powder and process until combined. Add remaining 3 tbsp milk, 1 tbsp at a time, scraping down sides
 after each addition. Once milk is incorporated, process for an additional 2 minutes. Spread icing over cupcakes.