So, what I got working for me is this:
public class RestaurantItemEntity : BaseEntity
{
[Column(TypeName = "VARCHAR(128)")]
[StringLength(128)]
[Required]
public string Name { get; set; }
[Column(TypeName = "VARCHAR(1024)")]
[StringLength(1024)]
public string Description { get; set; }
[Column(TypeName = "decimal(16,2)")]
[Required]
public decimal Price { get; set; }
[Required]
public RestaurantEntity Restaurant { get; set; }
}
This is EF Code first for .NET core.