How to do it...

1. Create a custom SceneComponent called ActorSpawnerComponent:

2. Make the following changes to the header:

#include "CoreMinimal.h"
#include "Components/SceneComponent.h"
#include "ActorSpawnerComponent.generated.h"


UCLASS( ClassGroup=(Custom), meta=(BlueprintSpawnableComponent) )
class CHAPTER_04_API UActorSpawnerComponent : public USceneComponent
{
  GENERATED_BODY()

public: 
  // Sets default values for this component's properties
  UActorSpawnerComponent();

  // Will spawn actor when called
  UFUNCTION(BlueprintCallable, Category=Cookbook)
  void Spawn();

  UPROPERTY(EditAnywhere)
  TSubclassOf<AActor> ActorToSpawn;

protected:
  // Called when the game starts
  virtual void BeginPlay() override;

public: 
  // Called every frame
  virtual void TickComponent(float DeltaTime, ELevelTick TickType, FActorComponentTickFunction* ThisTickFunction) override;

    
};

3. Add the following function implementation to the .cpp file:

void UActorSpawnerComponent::Spawn()
{
    UWorld* TheWorld = GetWorld();
    if (TheWorld != nullptr)
    {
        FTransform ComponentTransform(this->GetComponentTransform());
        TheWorld->SpawnActor(ActorToSpawn,&ComponentTransform);
    }
}

4. Compile and open your project. Drag an empty Actor into the scene and add your ActorSpawnerComponent to it. Select your new Component in the Details panel and assign a value to ActorToSpawn.

Now, whenever Spawn() is called on an instance of your component, it will instantiate a copy of the Actor class that's specified in ActorToSpawn.