Run 2 tasks independently, when 1 of them could exist or not

Ok, this question may be simple. I have the following code:

public async Task Start()
        {
            Remux();
            if (TransmitEnabled && userLogged)
                Transmit();
        }

private async Task Remux()
        {
        }

        private async Task Transmit()
        {
        }

As you see, there is not await keywork, but it should be one, right? I don't want to await Remux() in order to run the condition and Transmit statements, so how can I write this code in order to run the 2 tasks independently?

Take a look at WPF FlashMessage
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