Makes8 servings
                    
                
                
                    
                        
                            - Active time:20 min
 
                        
                            - Start to finish:1 1/4 hr
 
                        
                    
                
             
            
            
                
                
                
    
      
          
          
          
              
              
              
          
          
          
          
          
              
              
              October 2005
            
          
          
      
  
                
                
            
            
            
                This cake is the little black dress of fiber—velvety and sophisticated. Medjool dates lend it an unbelievably unctuous texture. When measuring spelt flour, be sure to spoon it into the measuring cup and level it off to prevent packing it down; this will keep the cake light.
            
            
            
            
            
                
                    
                    
                    
                        
                            
                            
                            
                                
                                    
                                        - 
                                            1 1/2
                                            
                                            sticks (3/4 cup) unsalted butter, softened, plus additional for pan
                                            
                                        
 
                                    
                                        - 
                                            3/4
                                            cup
                                            unsweetened Dutch-process cocoa powder plus additional for dusting pan and cake
                                            
                                        
 
                                    
                                        - 
                                            1
                                            cup
                                            boiling-hot water
                                            
                                        
 
                                    
                                        - 
                                            1 1/2
                                            tablespoons
                                            instant-espresso powder
                                            
                                        
 
                                    
                                        - 
                                            1 1/2
                                            teaspoons
                                            vanilla
                                            
                                        
 
                                    
                                        - 
                                            1
                                            teaspoon
                                            baking soda
                                            
                                        
 
                                    
                                        - 
                                            1/2
                                            lb
                                            Medjool dates (12 to 14), pitted and coarsely chopped (1 1/2 cups)
                                            
                                        
 
                                    
                                        - 
                                            2
                                            cups
                                            spelt flour
                                            
                                        
 
                                    
                                        - 
                                            2
                                            teaspoons
                                            baking powder
                                            
                                        
 
                                    
                                        - 
                                            3/4
                                            teaspoon
                                            salt
                                            
                                        
 
                                    
                                        - 
                                            1
                                            cup
                                            packed dark brown sugar
                                            
                                        
 
                                    
                                        - 
                                            2
                                            
                                            large eggs
                                            
                                        
 
                                    
                                
                            
                         
                    
                 
            
            
            
            
            
                
            
            
            
            
                
                    
                    
                    
                        
                            
                                
                                
                                
                                    
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Put oven rack in middle position and preheat oven to 350ºF. Butter springform pan, then lightly dust with cocoa powder, knocking out excess.
                                         
                                    
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Stir together boiling-hot water, espresso powder, vanilla, and baking soda in a bowl, then add dates, mashing lightly with a fork, and steep until liquid cools to room temperature, about 10 minutes.
                                         
                                    
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Whisk together spelt flour, cocoa powder, baking powder, and salt in another bowl. Beat together butter and brown sugar with an electric mixer at medium-high speed until pale and fluffy. Add eggs 1 at a time, beating until just combined. Beat in date mixture (batter will look curdled), then reduce speed to low and add flour mixture, mixing until just combined.
                                         
                                    
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Spoon batter into springform pan, smoothing top, and bake until a wooden pick or skewer inserted into center comes out clean, about 50 minutes to 1 hour. Cool cake in pan on a rack 5 minutes, then remove side of pan and cool cake on rack. Serve cake warm or at room temperature.