popcorn.js

/* Popular Ice Cream Totals Quiz
 *
 * Using the data array and .reduce():
 *   - Return an object where each property is the name of an ice cream flavor
 *     and each value is an integer that's the total count of that flavor
 *   - Store the returned data in a new iceCreamTotals variable
 *
 * Notes:
 *   - Do not delete the data variable
 *   - Do not alter any of the data content
 */

 const data = [
     { name: 'Tyler', favoriteIceCreams: ['Strawberry', 'Vanilla', 'Chocolate', 'Cookies & Cream'] },
     { name: 'Richard', favoriteIceCreams: ['Cookies & Cream', 'Mint Chocolate Chip', 'Chocolate', 'Vanilla'] },
     { name: 'Amanda', favoriteIceCreams: ['Chocolate', 'Rocky Road', 'Pistachio', 'Banana'] },
     { name: 'Andrew', favoriteIceCreams: ['Vanilla', 'Chocolate', 'Mint Chocolate Chip'] },
     { name: 'David', favoriteIceCreams: ['Vanilla', 'French Vanilla', 'Vanilla Bean', 'Strawberry'] },
     { name: 'Karl', favoriteIceCreams: ['Strawberry', 'Chocolate', 'Mint Chocolate Chip'] }
 ];
 
 let iceCreamTotals =data.reduce((acc, values ) => {
     
     values.favoriteIceCreams.forEach((name)=>{
        if (name in acc){
            acc[name]++;
        } else {
            acc[name] = 1;
        }   
     });
     
    return acc;

 } , {});
 

console.log(iceCreamTotals);

Thank you for posting this, it helped me grasp the reduce() function better.
My actual code for this problem is below

let iceCreamTotals = data.reduce((accumulator, item) =>{
    item.favoriteIceCreams.map(iceCream => accumulator[iceCream] = accumulator[iceCream]? accumulator[iceCream] + 1:1);
    return accumulator;
},{});
console.log(iceCreamTotals);