Build NuGet Package automatically including referenced dependencies

I want to run a local/internal NuGet repository. I think I've figured out how to "reuse" existing NuGet packages by including them in a dummy project using NuGet and scanning the package file to grab my locally-cached .nupkg files, but...

How do you create a nuget package (.nupkg) from a project, automatically including alldll dependencies and not just those grabbed via NuGet?

Specifically:

1. Create a solution
2. Add a new Project
3. Add references to various .dll files/other projects <-- this is the missing part
4. Add NuGet packages via package manager / cmdline / whatever
5. something automatically creates the .nupkg

From what I've found, you're supposed to do things like

• manually edit your .csproj file to add <BuildPackage>true</BuildPackage> to include dependencies
• manually create a .nuspec file and manually list your dependencies (similar ?)
• manually run nuget pack on your .nuspec file

But everything is manual, which is stupid. Even the semi-automatic solutions are still awkward or half-manual:

• Create .nuspec templates - doesn't seem to include dependencies, just metadata

• nuget pack via build-event (step #5), which you need to add manually to every project, and it has its own quirks:

  "$(SolutionDir).nuget\NuGet.exe" pack "$(ProjectPath)" -Properties Configuration=Releasemove /Y *.nupkg "$(TargetDir)"

I'll settle for something that automatically creates a .nuspec manifest from project references. Then theoretically that + the nuget build-event can be rolled up into a build-project/nuget package, which is what I really want to see.