Yes, you can. And it is not too easy.
Microfoam has small bubbles by definition and the panarello wand will draw a 'certain' amount of air and you can't really control that part. The notes below might help you get there. I have successfully done this with the panarello wands of automatic Saeco machines which aren't too different from deLonghi.
- Run your steam wand in a cup water first until it's fully producing steam and not spuddering hot water mixed with steam.
- Use a small Stainless Steel Milk Frothing Pitcher. If the wand is trying to blow steam and air in for a long time, you'll end up with big bubbles. That wand is not as powerful as a commercial espresso machine with a proper boiler.
- 'Stretch' the froth only for a few seconds in the beginning.
- Keep the wand off-center in the pitcher to encourage circulation (see next point).
- Most important: make sure you create a whirlpool to circulate the milk (helps to gently move the pitcher in a circular motion to encourage the start of the whirlpool).
- I use the fattiest milk I can find.
The trick is to move the milk in a circulation such that big bubbles
break and only microbubbles survive. Some microfoam creation also
happens at the vortex of the whirlpool.