```csharp
// DinnerPlanner.API (ASP.NET Core Web API)
// Domain Layer (DDD Core)
public class Recipe : Entity<Guid>
{
    public string Name { get; private set; }
    public string Description { get; private set; }
    public string Instructions { get; private set; }
    private readonly List<Ingredient> _ingredients = new();
    public IReadOnlyCollection<Ingredient> Ingredients => _ingredients.AsReadOnly();
    private readonly List<Tag> _tags = new();
    public IReadOnlyCollection<Tag> Tags => _tags.AsReadOnly();

    private Recipe() { } // For EF Core

    public Recipe(string name, string description, string instructions) 
    {
        Id = Guid.NewGuid();
        Name = name;
        Description = description;
        Instructions = instructions;
    }

    public void AddIngredient(string name)
    {
        _ingredients.Add(new Ingredient(name));
    }

    public void AddTag(string name)
    {
        _tags.Add(new Tag(name));
    }
}

public class Ingredient : ValueObject
{
    public string Name { get; }

    public Ingredient(string name)
    {
        Name = name;
    }

    protected override IEnumerable<object> GetEqualityComponents()
    {
        yield return Name;
    }
}

public class Tag : ValueObject
{
    public string Name { get; }

    public Tag(string name)
    {
        Name = name;
    }

    protected override IEnumerable<object> GetEqualityComponents()
    {
        yield return Name;
    }
}

// Application Layer (MediatR Handlers)
public class GetRecipesQuery : IRequest<List<RecipeDto>> { }

public class GetRecipesQueryHandler : IRequestHandler<GetRecipesQuery, List<RecipeDto>>
{
    private readonly IRecipeRepository _repository;

    public GetRecipesQueryHandler(IRecipeRepository repository)
    {
        _repository = repository;
    }

    public async Task<List<RecipeDto>> Handle(GetRecipesQuery request, CancellationToken cancellationToken)
    {
        var recipes = await _repository.GetAllAsync();
        return recipes.Select(r => new RecipeDto
        {
            Id = r.Id,
            Name = r.Name,
            Description = r.Description,
            Ingredients = r.Ingredients.Select(i => i.Name).ToList(),
            Instructions = r.Instructions,
            Tags = r.Tags.Select(t => t.Name).ToList()
        }).ToList();
    }
}

// Infrastructure Layer (EF Core)
public class RecipeRepository : IRecipeRepository
{
    private readonly DinnerPlannerDbContext _context;

    public RecipeRepository(DinnerPlannerDbContext context)
    {
        _context = context;
    }

    public async Task AddAsync(Recipe recipe)
    {
        await _context.Recipes.AddAsync(recipe);
        await _context.SaveChangesAsync();
    }

    public async Task<List<Recipe>> GetAllAsync()
    {
        return await _context.Recipes
            .Include(r => r.Ingredients)
            .Include(r => r.Tags)
            .ToListAsync();
    }
}

// API Layer (Controllers)
[ApiController]
[Route("api/[controller]")]
public class RecipesController : ControllerBase
{
    private readonly IMediator _mediator;

    public RecipesController(IMediator mediator)
    {
        _mediator = mediator;
    }

    [HttpGet]
    public async Task<ActionResult<List<RecipeDto>>> Get()
    {
        var recipes = await _mediator.Send(new GetRecipesQuery());
        return Ok(recipes);
    }

    [HttpPost]
    public async Task<ActionResult<RecipeDto>> Create(CreateRecipeCommand command)
    {
        var recipe = await _mediator.Send(command);
        return CreatedAtAction(nameof(Get), new { id = recipe.Id }, recipe);
    }
}

// Startup Configuration
public class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddDbContext<DinnerPlannerDbContext>(options =>
            options.UseSqlServer(Configuration.GetConnectionString("DefaultConnection")));

        services.AddScoped<IRecipeRepository, RecipeRepository>();
        
        services.AddMediatR(typeof(GetRecipesQueryHandler));
        
        services.AddControllers();
        services.AddSwaggerGen();
    }

    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        app.UseRouting();
        app.UseEndpoints(endpoints => endpoints.MapControllers());
        app.UseSwagger();
        app.UseSwaggerUI();
    }
}
```