using System;

using System.Linq.Expressions;

using System.Threading.Tasks;

using System.Linq;

public class Program

{

    public static void Main()

    {

        GetLotsOfStuff().Wait();

    }

    public static async Task GetLotsOfStuff()

    {

        int[] collection = {1,2,3};

        var tasks = collection.Select(q => GetDetailAboutTheThing(q));

        var things = await Task.WhenAll(tasks);

        foreach(var thing in things)

        {

            Console.WriteLine(thing);

        }

    }

    public static Task<int> GetDetailAboutTheThing(int i)

    {

        return Task.FromResult(i*2);    

    }

}

​