Heat a large Carbon Steel Frying Pan or Griddle over medium-high until hot.

Toss jalapeño in a little oil and lightly blister in the pan, turning occasionally to blister all sides, about 5 minutes. Set aside to cool, then roughly chop using a Chef Knife.

With Chef Knife, cut tomatillos into quarters for easy blending. Smash garlic using side of Knife. Halve, pit, and scoop out avocado flesh.

Add jalapeño, tomatillos, garlic, avocado, and cilantro to a high-speed blender or food processor and blend until smooth.

Add lime juice while blade is spinning  on low speed. Add salt. Taste and add more lime and/or salt, if desired. If salsa is too thick, add a little water to keep things moving. Once smooth, keep cold or use immediately.