ETA: This stitch can also be used when working in the round. It can replace “Ch 4 (counts as first tr)” in a pattern. /ETA

Here’s the treble crochet stitch at the beginning of the row. I did not invent this technique, but figured it out from a description (actually of the double).

Turn your work. Pull the loop to about the length of a tr. Hold the top of the loop with your index finger on the top of the hook. Here’s the trick… yarn over with the two strands of the LOOP twice. So now, you have the strand you’re holding with the index finger & four strands of the loop on the hook. Don’t let go for the stitch, but if you let your finger go, it just looks like you twisted the loop. Ok, to continue, yo with the new yarn & pull through the 2 strands of the loop, yo with the new yarn & pull through 3. Is your index finger still holding the top of the loop? Yes, good! Yo w/ the new yarn & pull through last 2 loops. Voila! A fully formed tr at the beginning of the row.

OK, here is the video link!

Also see the video for the double stitch.