How to ensure that Task.Factory.StartNew does not slow down the main thread?

Question

There are a bunch of compressed pieces of data that should be deflated asynchronously - without blocking or slowing down the main stream in any form or form.

Decompressed pieces will be used by the main thread as soon as they are unpacked.

I am currently doing it like this:

foreach (var chunkPair in compressedChunkData)
{                        
    var task = Task.Factory.StartNew<Chunk>(() =>
    {
        var compressedBytes = Convert.FromBase64String(chunkPair.Value);
        var chunk = Decompress(compressedBytes);
        return chunk;
    }).ContinueWith((finishedTask) =>
    {
        var chunk = finishedTask.Result;
        TaskFinishActions.Enqueue(() =>
        {
            chunk.PostSerialize();
            document.Chunks.Add(chunkPair.Key, chunk);
        });
    });
}
// By the time we get here 20ms has passed!!!

The problem is that it seems to capture the kernel that mainthread is running on, it improves performance.

Is there a way to TaskFactoryhave a thread to the kernel and a context switch from mainthread only in those short moments when mainthread is locked?

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EDIT2: , :

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Answer 1

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Answer 2

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Parallel.ForEach(compressedChunkData, chunkPair => {
    var compressedBytes = Convert.FromBase64String(chunkPair.Value);
    var chunk = Decompress(compressedBytes);
    TaskFinishActions.Enqueue(() => {
        chunk.PostSerialize();
        document.Chunks.Add(chunkPair.Key, chunk);
    });
});

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EDIT:

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