Minimal meal prep times for two stoves

mealPrep.js

/**
// Using number of minutes for prep time

mealPrep([120])
2 // one single long dish

mealPrep([30, 30, 30, 20])
2 // multiple shorter dishes
^
I don't understand, this should take 60 minutes.

mealPrep([30, 25, 45, 30, 60, 15])
3 // many dishes with varying times
^
I don't understand. It should only take 105 minutes.
**/

function mealPrep(prepTimes) {
  var total = prepTimes.reduce((a,b)=>a+b, 0);
  var halfTime = total/2;
  
  function recur(total, remaining) {
    if(total<halfTime) return;
    if(remaining.length === 0) return total;
    var rest = remaining.slice(1)
    var include = recur(total, rest);
    var exclude = recur(total-remaining[0], rest);
    if(!include)
        return exclude;
    if(!exclude)
        return include;
    if(include < exclude)
        return include;
    return exclude;
  }
  return Math.ceil(recur(total, prepTimes)/60);
}