Asynchronous task in asp .net MVC 5

Question

I am trying to use async, await and task to implement one of an asynchronous requirement in my web application. I have below code in my controller class. What I want is that after the flow reaches to printing "controller 1", the system starts the business method on a separate thread and without waiting for the response system should reach to print statement in controller and print "controller 2". But when I am executing the below code I am getting output pattern as this-

controller 1
PlandesignBS
controller 2

Whereas I am expecting this-

controller 1
controller 2 (Flow should reach here immediately rather than waiting 
               for business methods to get executed First)

Contoller Class Code-

public class PlanDetailsController : Controller
{      
    [HttpPost]
    public async Task<ActionResult> Generate(PlanDetailsVM planDetailsVM) 
    {
       System.Diagnostics.Debug.WriteLine("controller 1");
       //calls business method to generate                       
       quoteId = await Task.Run(() => _planDesignBS.GenerateBS(planDetailsVM));
       System.Diagnostics.Debug.WriteLine("controller 2");

        return Json(quoteId , JsonRequestBehavior.AllowGet);
    }
}

Business Method Code-

public int GenerateBS(PandetailsDTO plandetails)
{
  System.Diagnostics.Debug.WriteLine("PlandesignBS");

 //STEP 1-> call to dataLogic Layer to use Entity Framework

 // STEP 2-> call to a method (this method is part of dll used 
 //in our project and we don't have any control on it)

 return quoteId
}

EDIT: The reason I am trying to do this is that I want to use few http Posts requests from my client side. Suppose I call the Generate action method first from my client side and then don't want to wait for the response of it and at the same time want to invoke another http post.

EDIT: Including EF code where I am getting execption when I am trying to follow few solutions.This method will be called from my GenerateBS method. I am getting exception on this line inside getSICCode method-

 DbContext.Database.ExecuteSqlCommand("spGET_SICCode @industryClasifID,@industrySubClasifID,@SICCode OUTPUT", industryClasifID, industrySubClasifID, SICCode); 

EF Code-

 public class PlanDesignRepository : Repository<myobject>, IPlanDesignRepository
{
    private IDbSet<myobject> _dbSet;
    private DbContext _dbContext;

    private IDbSet<myobject> DbSet
    {
        get
        {
            if (_dbSet == null)
            {
                _dbSet = base.UnitOfWork.Context.Set<myobject>();
            }
            return _dbSet;
        }
    }

    private DbContext DbContext
    {
        get
        {
            if (_dbContext == null)
            {
                _dbContext = base.UnitOfWork.Context;
            }
            return _dbContext;
        }
    }
 public string GetSICCode(IndustryClassficDO industryClassficDO)
    {

        SqlParameter industryClasifID = new SqlParameter("industryClasifID", SqlDbType.Int);
        industryClasifID.Value = industryClassficDO.IndustryClassificationId;

        SqlParameter industrySubClasifID = new SqlParameter("industrySubClasifID", SqlDbType.Int);
        industrySubClasifID.Value = industryClassficDO.IndustrySubClassificationId;

        SqlParameter SICCode = new SqlParameter("SICCode", SqlDbType.VarChar, 10);
        SICCode.Direction = ParameterDirection.Output;

        DbContext.Database.ExecuteSqlCommand("spGET_SICCode @industryClasifID,@industrySubClasifID,@SICCode OUTPUT", industryClasifID, industrySubClasifID, SICCode);            


        return (string)(SICCode.Value);
    }
  }

EDIT: I have few http Post calls as shown below-

  AngularJS code for AJAX calls:

 $http({
 url: key_Url_Generate,
 method: Post,
 params: $scope.PlanDetails
        }).then(function (result) {
                 //Notify user for success or failure
                                  } 

Answer 1

The usage of await means that you are waiting for the task to complete before continuing the code. If you want it to execute simultaneously with the other code you should change it like this

public class PlanDetailsController : Controller
{      
    [HttpPost]
    public async Task<ActionResult> Generate(PlanDetailsVM planDetailsVM) 
    {
       System.Diagnostics.Debug.WriteLine("controller 1");
       //calls business method to generate                       
       var task = Task.Run(() => _planDesignBS.GenerateBS(planDetailsVM));
       System.Diagnostics.Debug.WriteLine("controller 2");

        var quoteId = await task;
        return Json(quoteId , JsonRequestBehavior.AllowGet);
    }
}

However I wouldn't recommend this as it serves no purpose and can degrade performance via starving the ASP.NET thread pool of threads. Why do you want to do this anyway?