JavaScript Chaining

const restaurant = {
  name: 'Classico Italiano',
  location: 'Via Angelo Tavanti 23, Firenze, Italy',
  categories: ['Italian', 'Pizzeria', 'Vegetarian', 'Organic'],
  starterMenu: ['Focaccia', 'Bruschetta', 'Garlic Bread', 'Caprese Salad'],
  mainMenu: ['Pizza', 'Pasta', 'Risotto'],
  operatingHours: {
    thu: {
      open: 12,
      close: 22,
    },
    fri: {
      open: 11,
      close: 23,
    },
    sat: {
      open: 0,
      close: 24
    },
  },
  order: function (starterIndex, mainIndex) {
    return [this.starterMenu[starterIndex], this.mainMenu[mainIndex]]
  },
  orderDelivery({
                  starterIndex = 1,
                  mainIndex = 0,
                  time = '20:00',
                  address,
                }) {
    console.log(`Order recieved! ${this.starterMenu[starterIndex]}  and ${this.mainMenu[mainIndex]} will be delivers to ${address} at ${time}`)
  },
  orderPasta(ing1, ing2, ing3) {
    console.log(`Here is your delicious pasta with ${ing1}, ${ing2}, and ${ing3}.`)
  },
  orderPizza(mainIngredient, ...additionalIngredients) {
// just going to log them here, but really you'd do something with the ingredients
    console.log(mainIngredient)
    console.log(additionalIngredients)
  },
}

console.log(restaurant.operatingHours.mon)        // undefined
console.log(restaurant.operatingHours.mon.open)   // error --  can't read property of undefined