Set Up:

Start standing with feet under your hips (or full together)

Forward fold, reaching down to touch your toes (or as close as possible). Keep legs straight.

Reach hands towards ground. If small knee bend is required due to tight hamstrings, that is fine.

Place hands on the ground and start walking them outward.

Walk hands out to stack under shoulders (regular plank hold) or ideally past your shoulders to create a long hollow body plank.

Protract (round) shoulders, tuck ribs and hips under, squeeze glutes

The further you walk your hands, the harder it will become on your core and shoulders. Only walk as far as a quality hollow position can be maintained.
After holding your end range, start walking feet back in, ending back in the forward fold.