Serves8 to 10
                    
                
                
                    
                        
                            - Active time:25 min
 
                        
                            - Start to finish:45 min
 
                        
                    
                
             
            
            
                
                
                
    
      
          
          
          
              
              
              
          
          
          
          
          
              
              
              November 2003
            
          
          
      
  
                
                
            
            
            
                We strongly recommend using light-colored metal (including nonstick) shallow baking pans (1 large or 2 small) for this recipe. When we used dark baking pans, the potatoes blackened before they were completely cooked through.
            
            
            
            
            
                
                    
                    
                    
                        
                            
                            
                            
                                
                                    
                                        - 
                                            3
                                            lb
                                            medium sweet potatoes, peeled and each cut lengthwise into 8 spears
                                            
                                        
 
                                    
                                        - 
                                            1/4
                                            cup
                                            vegetable oil
                                            
                                        
 
                                    
                                        - 
                                            1 1/4
                                            teaspoons
                                            salt
                                            
                                        
 
                                    
                                        - 
                                            5
                                            tablespoons
                                            unsalted butter
                                            
                                        
 
                                    
                                        - 
                                            1/3
                                            cup
                                            molasses (not robust or blackstrap) 
                                            
                                        
 
                                    
                                        - 
                                            1/3
                                            cup
                                            bottled horseradish (including juice; 3 oz)
                                            
                                        
 
                                    
                                
                            
                         
                    
                 
            
            
            
            
            
            
            
            
                
                    
                    
                    
                        
                            
                                
                                
                                
                                    
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Put oven rack in lower third of oven and preheat oven to 450ºF.
                                         
                                    
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If potato spears are very long, halve them diagonally. Toss potatoes with oil and 3/4 teaspoon salt in a large bowl, then spread in 1 layer in a large shallow baking pan (1 inch deep). Roast in lower third of oven, turning once or twice, until tender, 18 to 22 minutes. Leave oven on.
                                         
                                    
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While potatoes roast, bring butter, molasses, horseradish (with juice), and remaining 1/2 teaspoon salt to a boil in a small heavy saucepan, stirring, then reduce heat and simmer, stirring occasionally, until slightly thickened and reduced to about 3/4 cup, about 5 minutes.
                                         
                                    
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Transfer mixture to a blender and purée 30 seconds (use caution when blending hot liquids). Pour glaze through a fine-mesh sieve into a heatproof bowl, pressing on and discarding solids. Drizzle glaze over cooked sweet potatoes and gently toss until coated.
                                         
                                    
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Just before serving, bake glazed sweet potatoes in lower third of oven until hot, 3 to 5 minutes.
                                         
                                    
                                
                             
                        
                    
                    Cooks’ note: Sweet potatoes can be roasted 2 hours ahead. Toss with glaze and reheat just before serving.