Thanks to Titanium Goat miracle foil!
I made my own cone, to fit a Tibetan 1,1l pot and added an inferno-like insert. ConeLayout for design, scissors, Dremel for the harder job and hole punch for the easy holes...
Tested and approved last week in Brittany.

Burning fast:

Insert:

The grate uses 2 metal rods, same method as pot support (2 tent pegs)

The whole lot, unfolded:

And folded for transport:

Titanium foil being very resilient, it can be rolled very tight, and snaps easily back into shape.

The cone is just high enough to be used with a flatish ordinary can stove; It weights around 1.3 oz (35 gr)...