Pizza challenge

pizza.js

const defer = (res, ms) => new Promise(resolve => setTimeout(() => resolve(res), ms));
                                                                                        
const makeDough = () => defer({add: () => {}}, 500);                                    
const makeSauce = () => defer({determineCheese: () => 'cheddar'}, 250);                 
const grateCheese = () => defer({type: 'cheddar'}, 150);                                
                                                                                        
                                                                                        
async function makePizza(sauceType = 'red') {                                           
                                                                                                               
  const pDough = makeDough();                                                           
  const pSauce = makeSauce(sauceType);                                                  
  const pCheese = pSauce.then(sauce => grateCheese(sauce.determineCheese()));  
                                                                                        
  const [dough, sauce, cheese] = await Promise.all([pDough, pSauce, pCheese]);          
                                                                                        
  dough.add(sauce);                                                                     
  dough.add(cheese);                                                                    
                                                                                        
  return dough;                                                                         
}                                                                                       
                                                                                        
makePizza();